Here \(\alpha+\beta=6\) and \(\alpha^2+\beta^2=26\). From \(36-2\alpha\beta=26\), \(\alpha\beta=5\), so the roots are (1) and (5).
Step 2
Why this answer is correct
The correct answer is A. (1) और (5) / (1) and (5). Here \(\alpha+\beta=6\) and \(\alpha^2+\beta^2=26\). From \(36-2\alpha\beta=26\), \(\alpha\beta=5\), so the roots are (1) and (5).
Step 3
Exam Tip
\(\alpha+\beta=6\) और \(\alpha^2+\beta^2=26\) है। \(36-2\alpha\beta=26\) से \(\alpha\beta=5\), इसलिए जड़ें (1) और (5) हैं।
For both roots to be negative, the sum (-12) and product \(\lambda>0\) are needed. For real distinct roots, \(144-4\lambda>0\), so \(0<\lambda<36\).
Step 2
Why this answer is correct
The correct answer is A. \(0<\lambda<36\). For both roots to be negative, the sum (-12) and product \(\lambda>0\) are needed. For real distinct roots, \(144-4\lambda>0\), so \(0<\lambda<36\).
Step 3
Exam Tip
दोनों ऋणात्मक जड़ों के लिए योग (-12) और गुणनफल \(\lambda>0\) चाहिए। वास्तविक भिन्न जड़ों के लिए \(144-4\lambda>0\), इसलिए \(0<\lambda<36\)।
Here \(\alpha+\beta=5\) and \(\alpha\beta=6\). The new roots are (5) and (6), so the equation is \(x^2-11x+30=0\).
Step 2
Why this answer is correct
The correct answer is A. \(x^2-11x+30=0\). Here \(\alpha+\beta=5\) and \(\alpha\beta=6\). The new roots are (5) and (6), so the equation is \(x^2-11x+30=0\).
Step 3
Exam Tip
\(\alpha+\beta=5\) और \(\alpha\beta=6\) हैं। नई जड़ें (5) और (6) हैं, इसलिए समीकरण \(x^2-11x+30=0\) है।
Here \(\alpha+\beta=5\) and \(\alpha^2+\beta^2=17\). From \(25-2\alpha\beta=17\), \(\alpha\beta=4\), so the roots are (1) and (4).
Step 2
Why this answer is correct
The correct answer is A. (1) और (4) / (1) and (4). Here \(\alpha+\beta=5\) and \(\alpha^2+\beta^2=17\). From \(25-2\alpha\beta=17\), \(\alpha\beta=4\), so the roots are (1) and (4).
Step 3
Exam Tip
\(\alpha+\beta=5\) और \(\alpha^2+\beta^2=17\) है। \(25-2\alpha\beta=17\) से \(\alpha\beta=4\), इसलिए जड़ें (1) और (4) हैं।
For both roots to be negative, the sum (-10) and product \(\lambda>0\) are needed. For real distinct roots, \(100-4\lambda>0\), hence \(0<\lambda<25\).
Step 2
Why this answer is correct
The correct answer is B. \(0<\lambda<25\). For both roots to be negative, the sum (-10) and product \(\lambda>0\) are needed. For real distinct roots, \(100-4\lambda>0\), hence \(0<\lambda<25\).
Step 3
Exam Tip
दोनों ऋणात्मक जड़ों के लिए योग (-10) और गुणनफल \(\lambda>0\) चाहिए। वास्तविक भिन्न जड़ों के लिए \(100-4\lambda>0\), इसलिए \(0<\lambda<25\)।
Here \(\alpha+\beta=4\) and \(\alpha^2+\beta^2=10\). From \(16-2\alpha\beta=10\), \(\alpha\beta=3\), so the roots are (1) and (3).
Step 2
Why this answer is correct
The correct answer is A. (1) और (3) / (1) and (3). Here \(\alpha+\beta=4\) and \(\alpha^2+\beta^2=10\). From \(16-2\alpha\beta=10\), \(\alpha\beta=3\), so the roots are (1) and (3).
Step 3
Exam Tip
\(\alpha+\beta=4\) और \(\alpha^2+\beta^2=10\) है। \(16-2\alpha\beta=10\) से \(\alpha\beta=3\), इसलिए जड़ें (1) और (3) हैं।
For both roots to be negative, the sum (-2) and product \(\lambda>0\) are needed. For real distinct roots, \(4-4\lambda>0\), hence \(0<\lambda<1\).
Step 2
Why this answer is correct
The correct answer is A. \(0<\lambda<1\). For both roots to be negative, the sum (-2) and product \(\lambda>0\) are needed. For real distinct roots, \(4-4\lambda>0\), hence \(0<\lambda<1\).
Step 3
Exam Tip
दोनों ऋणात्मक जड़ों के लिए योग (-2) और गुणनफल \(\lambda>0\) चाहिए। वास्तविक भिन्न जड़ों के लिए \(4-4\lambda>0\), इसलिए \(0<\lambda<1\)।
Here \(\alpha+\beta=3\) and \(\alpha\beta=-2\). Thus \(\alpha^2+\beta^2=13\) and \(\alpha^2\beta^2=4\), so the equation is \(x^2-13x+4=0\).
Step 2
Why this answer is correct
The correct answer is A. \(x^2-13x+4=0\). Here \(\alpha+\beta=3\) and \(\alpha\beta=-2\). Thus \(\alpha^2+\beta^2=13\) and \(\alpha^2\beta^2=4\), so the equation is \(x^2-13x+4=0\).
Step 3
Exam Tip
\(\alpha+\beta=3\) और \(\alpha\beta=-2\) है। इसलिए \(\alpha^2+\beta^2=13\) और \(\alpha^2\beta^2=4\), अतः समीकरण \(x^2-13x+4=0\) है।
Here \(\alpha+\beta=\frac{10}{3}\) and \(\alpha\beta=1\). The reciprocal roots also have sum \(\frac{10}{3}\) and product (1).
Step 2
Why this answer is correct
The correct answer is A. \(3x^2-10x+3=0\). Here \(\alpha+\beta=\frac{10}{3}\) and \(\alpha\beta=1\). The reciprocal roots also have sum \(\frac{10}{3}\) and product (1).
Step 3
Exam Tip
यहाँ \(\alpha+\beta=\frac{10}{3}\) और \(\alpha\beta=1\) है। व्युत्क्रम जड़ों का योग \(\frac{10}{3}\) और गुणनफल (1) ही रहता है।
(\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta). Here (\left\(-\frac{7}{6}\right\)2-2\cdot\frac{1}{3}=\frac{25}{36}).
Step 2
Why this answer is correct
The correct answer is A. \( \frac{25}{36} \). (\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta). Here (\left\(-\frac{7}{6}\right\)2-2\cdot\frac{1}{3}=\frac{25}{36}).
Step 3
Exam Tip
(\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta) होता है। यहाँ (\left\(-\frac{7}{6}\right\)2-2\cdot\frac{1}{3}=\frac{25}{36})।
(\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta). Here (\left\(-\frac{6}{5}\right\)2-2\cdot\frac{1}{5}=\frac{26}{25}).
Step 2
Why this answer is correct
The correct answer is A. \( \frac{26}{25} \). (\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta). Here (\left\(-\frac{6}{5}\right\)2-2\cdot\frac{1}{5}=\frac{26}{25}).
Step 3
Exam Tip
(\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta) होता है। यहाँ (\left\(-\frac{6}{5}\right\)2-2\cdot\frac{1}{5}=\frac{26}{25})।
If the roots are \(\alpha,\beta\), then (\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta). Here (\left\(-\frac{8}{3}\right\)2-2\cdot\frac{4}{3}=\frac{40}{9}).
Step 2
Why this answer is correct
The correct answer is A. \( \frac{40}{9} \). If the roots are \(\alpha,\beta\), then (\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta). Here (\left\(-\frac{8}{3}\right\)2-2\cdot\frac{4}{3}=\frac{40}{9}).
Step 3
Exam Tip
यदि मूल \(\alpha,\beta\) हैं, तो (\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta)। यहाँ (\left\(-\frac{8}{3}\right\)2-2\cdot\frac{4}{3}=\frac{40}{9})।
If the roots are \(\alpha,\beta\), then (\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta). Here (\left\(-\frac{7}{2}\right\)2-2\cdot\frac{3}{2}=\frac{37}{4}).
Step 2
Why this answer is correct
The correct answer is A. \( \frac{37}{4} \). If the roots are \(\alpha,\beta\), then (\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta). Here (\left\(-\frac{7}{2}\right\)2-2\cdot\frac{3}{2}=\frac{37}{4}).
Step 3
Exam Tip
यदि मूल \(\alpha,\beta\) हैं, तो (\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta)। यहाँ (\left\(-\frac{7}{2}\right\)2-2\cdot\frac{3}{2}=\frac{37}{4})।
A. वास्तविक, परिमेय और भिन्न/Real, rational and distinct
Step 1
Concept
A positive perfect square (D) gives real, rational and distinct roots. Check both the sign and perfect square condition of (D).
Step 2
Why this answer is correct
The correct answer is A. वास्तविक, परिमेय और भिन्न / Real, rational and distinct. A positive perfect square (D) gives real, rational and distinct roots. Check both the sign and perfect square condition of (D).
Step 3
Exam Tip
धनात्मक पूर्ण वर्ग (D) से वास्तविक, परिमेय और भिन्न मूल मिलते हैं। (D) का चिन्ह और पूर्ण वर्ग दोनों देखें।
A. यदि प्राकृतिक संख्या पूर्ण वर्ग नहीं है और अभाज्य है, तो उसका वर्गमूल अपरिमेय होता है/If a natural number is not a perfect square and is prime, its square root is irrational
Step 1
Concept
(2,3,5) are not perfect squares and are prime.
Step 2
Why this answer is correct
Assuming their square roots rational creates a common-factor contradiction.
Step 3
Exam Tip
Identifying perfect squares is the first task in such questions. चरण 1: (2,3,5) पूर्ण वर्ग नहीं हैं और अभाज्य हैं। चरण 2: इनके वर्गमूल को परिमेय मानने पर साझा गुणनखंड का विरोधाभास मिलता है। चरण 3: पूर्ण वर्ग पहचानना ऐसे प्रश्नों में पहला काम है।
The old sum is (4) and product is (3). The new sum is (12) and product is (27), so the equation is \(x^2-12x+27=0\).
Step 2
Why this answer is correct
The correct answer is A. \(x^2-12x+27=0\). The old sum is (4) and product is (3). The new sum is (12) and product is (27), so the equation is \(x^2-12x+27=0\).
Step 3
Exam Tip
पुराने योग (4) और गुणनफल (3) हैं। नए योग (12) और गुणनफल (27) होंगे इसलिए \(x^2-12x+27=0\) है।
The old sum is (3) and product is (2). The new sum is (6) and product is (8), so the equation is \(x^2-6x+8=0\).
Step 2
Why this answer is correct
The correct answer is A. \(x^2-6x+8=0\). The old sum is (3) and product is (2). The new sum is (6) and product is (8), so the equation is \(x^2-6x+8=0\).
Step 3
Exam Tip
पुराने योग (3) और गुणनफल (2) हैं। नए योग (6) और गुणनफल (8) होंगे इसलिए \(x^2-6x+8=0\) है।
The sum of new roots is (4\alpha+4\beta=4\(\alpha+\beta\)=12). When roots are multiplied by a factor, the sum is also multiplied by that factor.
Step 2
Why this answer is correct
The correct answer is A. (12). The sum of new roots is (4\alpha+4\beta=4\(\alpha+\beta\)=12). When roots are multiplied by a factor, the sum is also multiplied by that factor.
Step 3
Exam Tip
नए मूलों का योग (4\alpha+4\beta=4\(\alpha+\beta\)=12) है। गुणक लगे मूलों में योग भी उसी गुणक से गुणा होता है।
The sum of new roots is (3\alpha+3\beta=3\(\alpha+\beta\)=12). When roots are multiplied by a factor, the sum is multiplied by the same factor.
Step 2
Why this answer is correct
The correct answer is A. (12). The sum of new roots is (3\alpha+3\beta=3\(\alpha+\beta\)=12). When roots are multiplied by a factor, the sum is multiplied by the same factor.
Step 3
Exam Tip
नए मूलों का योग (3\alpha+3\beta=3\(\alpha+\beta\)=12) है। गुणक लगे मूलों में योग पर भी वही गुणक लगता है।
The sum of new roots is (2\alpha+2\beta=2\(\alpha+\beta\)=10). When roots are multiplied by a factor, the sum is also multiplied by that factor.
Step 2
Why this answer is correct
The correct answer is A. (10). The sum of new roots is (2\alpha+2\beta=2\(\alpha+\beta\)=10). When roots are multiplied by a factor, the sum is also multiplied by that factor.
Step 3
Exam Tip
नए मूलों का योग (2\alpha+2\beta=2\(\alpha+\beta\)=10) है। गुणक लगे मूलों में योग पर भी वही गुणक लगता है।
A. \(k\neq0\) और \(k^2\le16\)/\(k\neq0\) and \(k^2\le16\)
Step 1
Concept
For reciprocal roots, \(\frac{k}{k}=1\), so \(k\neq0\) is needed. For real roots, \(64-4k^2\ge0\), hence \(k^2\le16\).
Step 2
Why this answer is correct
The correct answer is A. \(k\neq0\) और \(k^2\le16\) / \(k\neq0\) and \(k^2\le16\). For reciprocal roots, \(\frac{k}{k}=1\), so \(k\neq0\) is needed. For real roots, \(64-4k^2\ge0\), hence \(k^2\le16\).
Step 3
Exam Tip
व्युत्क्रम जड़ों के लिए \(\frac{k}{k}=1\) है, इसलिए \(k\neq0\) चाहिए। वास्तविक जड़ों के लिए \(64-4k^2\ge0\), अतः \(k^2\le16\)।
A positive product means both roots have the same sign. A negative sum means both roots are negative.
Step 2
Why this answer is correct
The correct answer is B. दोनों ऋणात्मक / Both negative. A positive product means both roots have the same sign. A negative sum means both roots are negative.
Step 3
Exam Tip
गुणनफल धनात्मक होने पर दोनों मूलों का चिन्ह समान होता है। योग ऋणात्मक होने से दोनों मूल ऋणात्मक होंगे।
A. कथन और कारण दोनों सही हैं/Both assertion and reason are correct
Step 1
Concept
Here (D=32-4(1)(7)=-19). Since (D<0), the assertion is correct.
Step 2
Why this answer is correct
The correct answer is A. कथन और कारण दोनों सही हैं / Both assertion and reason are correct. Here (D=32-4(1)(7)=-19). Since (D<0), the assertion is correct.
Step 3
Exam Tip
यहाँ (D=32-4(1)(7)=-19) है। (D<0) होने से कथन सही है।
A. \(k\neq0\) और \(k^2\le36\)/\(k\neq0\) and \(k^2\le36\)
Step 1
Concept
The product of roots is \(\frac{k}{k}=1\), so \(k\neq0\) is needed. For real roots, \(144-4k^2\ge0\), hence \(k^2\le36\).
Step 2
Why this answer is correct
The correct answer is A. \(k\neq0\) और \(k^2\le36\) / \(k\neq0\) and \(k^2\le36\). The product of roots is \(\frac{k}{k}=1\), so \(k\neq0\) is needed. For real roots, \(144-4k^2\ge0\), hence \(k^2\le36\).
Step 3
Exam Tip
जड़ों का गुणनफल \(\frac{k}{k}=1\) है, इसलिए \(k\neq0\) चाहिए। वास्तविक जड़ों के लिए \(144-4k^2\ge0\), अतः \(k^2\le36\)।
C. \(k\neq0\) और \(k^2\le25\)/\(k\neq0\) and \(k^2\le25\)
Step 1
Concept
The product of roots is \(\frac{k}{k}=1\), so \(k\neq0\) is needed. For real roots, \(100-4k^2\ge0\), hence \(k^2\le25\).
Step 2
Why this answer is correct
The correct answer is C. \(k\neq0\) और \(k^2\le25\) / \(k\neq0\) and \(k^2\le25\). The product of roots is \(\frac{k}{k}=1\), so \(k\neq0\) is needed. For real roots, \(100-4k^2\ge0\), hence \(k^2\le25\).
Step 3
Exam Tip
जड़ों का गुणनफल \(\frac{k}{k}=1\) है, इसलिए \(k\neq0\) चाहिए। वास्तविक जड़ों के लिए \(100-4k^2\ge0\), अतः \(k^2\le25\)।
In the given equation, the sum of roots is (2r+5) and the product is (r-2+5r+6=(r+2)(r+3)). Hence the roots are (r+2) and (r+3), so the positive difference is (1).
Step 2
Why this answer is correct
The correct answer is A. (1). In the given equation, the sum of roots is (2r+5) and the product is (r-2+5r+6=(r+2)(r+3)). Hence the roots are (r+2) and (r+3), so the positive difference is (1).
Step 3
Exam Tip
दिए गए समीकरण में जड़ों का योग (2r+5) और गुणनफल (r-2+5r+6=(r+2)(r+3)) है। इसलिए जड़ें (r+2) और (r+3) हैं, अतः धनात्मक अंतर (1) है।
A. मूल एक दूसरे के विपरीत हैं/The roots are opposites of each other
Step 1
Concept
If \(\alpha+\beta=0\), then \(\beta=-\alpha\). Therefore the roots can be opposites.
Step 2
Why this answer is correct
The correct answer is A. मूल एक दूसरे के विपरीत हैं / The roots are opposites of each other. If \(\alpha+\beta=0\), then \(\beta=-\alpha\). Therefore the roots can be opposites.
Step 3
Exam Tip
यदि \(\alpha+\beta=0\) है तो \(\beta=-\alpha\) होता है। इसलिए मूल विपरीत हो सकते हैं।
Here \(\alpha^2+\beta^2=64-4=60\) and (\(\alpha\beta\)2=4). Thus \(\frac{1}{\alpha^2}+\frac{1}{\beta^2}=\frac{60}{4}=15\).
Step 2
Why this answer is correct
The correct answer is A. (15). Here \(\alpha^2+\beta^2=64-4=60\) and (\(\alpha\beta\)2=4). Thus \(\frac{1}{\alpha^2}+\frac{1}{\beta^2}=\frac{60}{4}=15\).
Step 3
Exam Tip
\(\alpha^2+\beta^2=64-4=60\) और (\(\alpha\beta\)2=4) है। इसलिए \(\frac{1}{\alpha^2}+\frac{1}{\beta^2}=\frac{60}{4}=15\)।
We use (\frac{1}{\alpha-2}+\frac{1}{\beta-2}=\frac{\alpha-2+\beta-2}{\(\alpha\beta\)2}). Since \(\alpha^2+\beta^2=30\) and (\(\alpha\beta\)2=9), the value is \(\frac{10}{3}\).
Step 2
Why this answer is correct
The correct answer is B. \(\frac{10}{3}\). We use (\frac{1}{\alpha-2}+\frac{1}{\beta-2}=\frac{\alpha-2+\beta-2}{\(\alpha\beta\)2}). Since \(\alpha^2+\beta^2=30\) and (\(\alpha\beta\)2=9), the value is \(\frac{10}{3}\).
Step 3
Exam Tip
(\frac{1}{\alpha-2}+\frac{1}{\beta-2}=\frac{\alpha-2+\beta-2}{\(\alpha\beta\)2}) होता है। \(\alpha^2+\beta^2=30\) और (\(\alpha\beta\)2=9), इसलिए मान \(\frac{10}{3}\) है।
We use (\frac{1}{\alpha-2}+\frac{1}{\beta-2}=\frac{\alpha-2+\beta-2}{\(\alpha\beta\)2}). Since \(\alpha^2+\beta^2=21\) and (\(\alpha\beta\)2=4), the value is \(\frac{21}{4}\).
Step 2
Why this answer is correct
The correct answer is A. \(\frac{21}{4}\). We use (\frac{1}{\alpha-2}+\frac{1}{\beta-2}=\frac{\alpha-2+\beta-2}{\(\alpha\beta\)2}). Since \(\alpha^2+\beta^2=21\) and (\(\alpha\beta\)2=4), the value is \(\frac{21}{4}\).
Step 3
Exam Tip
(\frac{1}{\alpha-2}+\frac{1}{\beta-2}=\frac{\alpha-2+\beta-2}{\(\alpha\beta\)2}) होता है। \(\alpha^2+\beta^2=21\) और (\(\alpha\beta\)2=4), इसलिए मान \(\frac{21}{4}\) है।
A. दो वास्तविक अपरिमेय और असमान/Two real irrational and distinct
Step 1
Concept
When (D>0), the roots are real and distinct. If (D) is not a perfect square, they are irrational.
Step 2
Why this answer is correct
The correct answer is A. दो वास्तविक अपरिमेय और असमान / Two real irrational and distinct. When (D>0), the roots are real and distinct. If (D) is not a perfect square, they are irrational.
Step 3
Exam Tip
(D>0) होने से मूल वास्तविक और असमान होते हैं। (D) पूर्ण वर्ग न हो तो वे अपरिमेय होते हैं।
A. वास्तविक, अपरिमेय और भिन्न/Real, irrational and distinct
Step 1
Concept
A positive non-perfect-square (D) gives real, irrational and distinct roots. Only (D>0) tells distinctness.
Step 2
Why this answer is correct
The correct answer is A. वास्तविक, अपरिमेय और भिन्न / Real, irrational and distinct. A positive non-perfect-square (D) gives real, irrational and distinct roots. Only (D>0) tells distinctness.
Step 3
Exam Tip
धनात्मक लेकिन अपूर्ण वर्ग (D) से मूल वास्तविक, अपरिमेय और भिन्न होते हैं। केवल (D>0) से भिन्नता पता चलती है।
The sum (-4) is already negative and the product must be positive, so (c>0). For real roots, \(16-4c\ge0\), hence \(0<c\le4\).
Step 2
Why this answer is correct
The correct answer is A. \(0<c\le4\). The sum (-4) is already negative and the product must be positive, so (c>0). For real roots, \(16-4c\ge0\), hence \(0<c\le4\).
Step 3
Exam Tip
योग (-4) पहले से ऋणात्मक है और गुणनफल धनात्मक चाहिए, इसलिए (c>0)। वास्तविक जड़ों के लिए \(16-4c\ge0\), अतः \(0<c\le4\)।
The sum of roots is \(\frac{1}{4+\sqrt{3}}+\frac{1}{4-\sqrt{3}}=\frac{8}{13}\). In \(x^2+ax+b=0\), the sum is (-a), so \(a=-\frac{8}{13}\).
Step 2
Why this answer is correct
The correct answer is A. -\(\frac{8}{13}\). The sum of roots is \(\frac{1}{4+\sqrt{3}}+\frac{1}{4-\sqrt{3}}=\frac{8}{13}\). In \(x^2+ax+b=0\), the sum is (-a), so \(a=-\frac{8}{13}\).
Step 3
Exam Tip
जड़ों का योग \(\frac{1}{4+\sqrt{3}}+\frac{1}{4-\sqrt{3}}=\frac{8}{13}\) है। \(x^2+ax+b=0\) में योग (-a) होता है, इसलिए \(a=-\frac{8}{13}\)।
The product of the two roots is (1), so the product condition is satisfied. For real roots, the discriminant \(s^2-4\ge0\), so \(s^2\ge4\).
Step 2
Why this answer is correct
The correct answer is A. \(s^2\ge4\). The product of the two roots is (1), so the product condition is satisfied. For real roots, the discriminant \(s^2-4\ge0\), so \(s^2\ge4\).
Step 3
Exam Tip
दोनों जड़ों का गुणनफल (1) है, इसलिए समीकरण का गुणनफल सही है। वास्तविक जड़ों के लिए विविक्तकर \(s^2-4\ge0\), इसलिए \(s^2\ge4\)।
The sum of these roots is \(\frac{5t+3}{4}\), and the product is (\frac{t(t+3)}{4}). These match \(-\frac{b}{a}\) and \(\frac{c}{a}\) of the given equation.
Step 2
Why this answer is correct
The correct answer is A. हर (t) के लिए / For every (t). The sum of these roots is \(\frac{5t+3}{4}\), and the product is (\frac{t(t+3)}{4}). These match \(-\frac{b}{a}\) and \(\frac{c}{a}\) of the given equation.
Step 3
Exam Tip
इन जड़ों का योग \(\frac{5t+3}{4}\) और गुणनफल (\frac{t(t+3)}{4}) है। ये दिए गए समीकरण के \(-\frac{b}{a}\) और \(\frac{c}{a}\) से मेल खाते हैं।
The sum (6) is positive and (c>0) is needed for both positive roots. For real roots, \(36-4c\ge0\), so \(0<c\le9\).
Step 2
Why this answer is correct
The correct answer is A. \(0<c\le9\). The sum (6) is positive and (c>0) is needed for both positive roots. For real roots, \(36-4c\ge0\), so \(0<c\le9\).
Step 3
Exam Tip
योग (6) धनात्मक है और दोनों धनात्मक जड़ों के लिए (c>0) चाहिए। वास्तविक जड़ों के लिए \(36-4c\ge0\), इसलिए \(0<c\le9\)।
After rationalising, the sum of roots is \(\frac{3}{2}\). In \(x^2+ax+b=0\), the sum is (-a), so \(a=-\frac{3}{2}\).
Step 2
Why this answer is correct
The correct answer is A. \(-\frac{3}{2}\). After rationalising, the sum of roots is \(\frac{3}{2}\). In \(x^2+ax+b=0\), the sum is (-a), so \(a=-\frac{3}{2}\).
Step 3
Exam Tip
रैशनलाइज करने पर जड़ों का योग \(\frac{3}{2}\) मिलता है। \(x^2+ax+b=0\) में जड़ों का योग (-a) होता है, इसलिए \(a=-\frac{3}{2}\)।
We have \(\tan\theta\cdot\cot\theta=1\) and \(\tan\theta+\cot\theta=s\). For real values, \(s^2-4\ge0\), so \(s^2\ge4\).
Step 2
Why this answer is correct
The correct answer is C. \(s^2\ge4\). We have \(\tan\theta\cdot\cot\theta=1\) and \(\tan\theta+\cot\theta=s\). For real values, \(s^2-4\ge0\), so \(s^2\ge4\).
Step 3
Exam Tip
\(\tan\theta\cdot\cot\theta=1\) और \(\tan\theta+\cot\theta=s\) है। वास्तविक मानों के लिए \(s^2-4\ge0\), इसलिए \(s^2\ge4\)।
The sum of these two roots is \(\frac{4t+2}{3}\), and the product is (\frac{t(t+2)}{3}). These match \(-\frac{b}{a}\) and \(\frac{c}{a}\) of the given equation.
Step 2
Why this answer is correct
The correct answer is C. हर (t) पर / For every (t). The sum of these two roots is \(\frac{4t+2}{3}\), and the product is (\frac{t(t+2)}{3}). These match \(-\frac{b}{a}\) and \(\frac{c}{a}\) of the given equation.
Step 3
Exam Tip
इन दोनों जड़ों का योग \(\frac{4t+2}{3}\) और गुणनफल (\frac{t(t+2)}{3}) है। ये दिए गए समीकरण के \(-\frac{b}{a}\) और \(\frac{c}{a}\) से मेल खाते हैं।
The sum (5) is positive and product (c>0) is needed for both roots. For real roots, \(25-4c\ge0\), so \(0<c\le\frac{25}{4}\).
Step 2
Why this answer is correct
The correct answer is B. \(0<c\le\frac{25}{4}\). The sum (5) is positive and product (c>0) is needed for both roots. For real roots, \(25-4c\ge0\), so \(0<c\le\frac{25}{4}\).
Step 3
Exam Tip
योग (5) धनात्मक है और दोनों जड़ों के लिए गुणनफल (c>0) चाहिए। वास्तविक जड़ों के लिए \(25-4c\ge0\), इसलिए \(0<c\le\frac{25}{4}\)।
A. ऐसा कोई वास्तविक \(\theta\) नहीं/No such real \(\theta\)
Step 1
Concept
We would need \(\sin \theta+\cos \theta=4\), but its maximum is \(\sqrt{2}\). Therefore no real \(\theta\) is possible.
Step 2
Why this answer is correct
The correct answer is A. ऐसा कोई वास्तविक \(\theta\) नहीं / No such real \(\theta\). We would need \(\sin \theta+\cos \theta=4\), but its maximum is \(\sqrt{2}\). Therefore no real \(\theta\) is possible.
Step 3
Exam Tip
\(\sin \theta+\cos \theta=4\) होना पड़ेगा, पर इसका अधिकतम \(\sqrt{2}\) है। इसलिए ऐसा वास्तविक \(\theta\) संभव नहीं है।
The sum is \(\frac{3t+1}{2}\) and the product is (\frac{t(t+1)}{2}). These match \(-\frac{b}{a}\) and \(\frac{c}{a}\) for every (t).
Step 2
Why this answer is correct
The correct answer is A. हर (t) के लिए / For every (t). The sum is \(\frac{3t+1}{2}\) and the product is (\frac{t(t+1)}{2}). These match \(-\frac{b}{a}\) and \(\frac{c}{a}\) for every (t).
Step 3
Exam Tip
इन जड़ों का योग \(\frac{3t+1}{2}\) और गुणनफल (\frac{t(t+1)}{2}) है। ये दिए गए समीकरण के \(-\frac{b}{a}\) और \(\frac{c}{a}\) से हर (t) पर मेल खाते हैं।
Use (\(\alpha-\beta\)2=\(\alpha+\beta\)2-4\alpha\beta). Since (16=\(\alpha+\beta\)2-20), we get (\(\alpha+\beta\)2=36) and \(m^2=36\).
Step 2
Why this answer is correct
The correct answer is C. (36). Use (\(\alpha-\beta\)2=\(\alpha+\beta\)2-4\alpha\beta). Since (16=\(\alpha+\beta\)2-20), we get (\(\alpha+\beta\)2=36) and \(m^2=36\).
Step 3
Exam Tip
(\(\alpha-\beta\)2=\(\alpha+\beta\)2-4\alpha\beta) लगाएँ। (16=\(\alpha+\beta\)2-20), इसलिए (\(\alpha+\beta\)2=36) और \(m^2=36\)।
The sum is \(\frac{5}{4}\) and the product is \(\frac{3}{8}\). Multiply \(x^2-\frac{5}{4}x+\frac{3}{8}=0\) by (8).
Step 2
Why this answer is correct
The correct answer is A. \(8x^2-10x+3=0\). The sum is \(\frac{5}{4}\) and the product is \(\frac{3}{8}\). Multiply \(x^2-\frac{5}{4}x+\frac{3}{8}=0\) by (8).
Step 3
Exam Tip
जड़ों का योग \(\frac{5}{4}\) और गुणनफल \(\frac{3}{8}\) है। समीकरण \(x^2-\frac{5}{4}x+\frac{3}{8}=0\) को (8) से गुणा करें।
Here \(\alpha+\beta=\frac{5}{2}\) and \(\alpha\beta=\frac{m}{2}\). Using (\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta), we get (m=3).
Step 2
Why this answer is correct
The correct answer is B. (3). Here \(\alpha+\beta=\frac{5}{2}\) and \(\alpha\beta=\frac{m}{2}\). Using (\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta), we get (m=3).
Step 3
Exam Tip
यहाँ \(\alpha+\beta=\frac{5}{2}\) और \(\alpha\beta=\frac{m}{2}\) है। (\alpha-2+\beta-2=\(\alpha+\beta\)2-2\alpha\beta) से (m=3) मिलता है।
A. दो वास्तविक परिमेय और असमान ((D=1))/Two real rational and distinct ((D=1))
Step 1
Concept
Here (D=(-11)2-4(2)(15)=1). A positive perfect-square (D) gives rational distinct roots.
Step 2
Why this answer is correct
The correct answer is A. दो वास्तविक परिमेय और असमान ((D=1)) / Two real rational and distinct ((D=1)). Here (D=(-11)2-4(2)(15)=1). A positive perfect-square (D) gives rational distinct roots.
Step 3
Exam Tip
यहाँ (D=(-11)2-4(2)(15)=1) है। धनात्मक पूर्ण वर्ग (D) परिमेय असमान मूल देता है।
A. वास्तविक, अपरिमेय और भिन्न/Real, irrational and distinct
Step 1
Concept
Here (D=\(2\sqrt{5}\)2-4(1)(1)=16>0). The roots are \(\sqrt{5}\pm2\), so they are irrational and distinct.
Step 2
Why this answer is correct
The correct answer is A. वास्तविक, अपरिमेय और भिन्न / Real, irrational and distinct. Here (D=\(2\sqrt{5}\)2-4(1)(1)=16>0). The roots are \(\sqrt{5}\pm2\), so they are irrational and distinct.
Step 3
Exam Tip
यहाँ (D=\(2\sqrt{5}\)2-4(1)(1)=16>0) है। मूल \(\sqrt{5}\pm2\) होंगे, इसलिए वे अपरिमेय और भिन्न हैं।
A. वास्तविक, अपरिमेय और भिन्न/Real, irrational and distinct
Step 1
Concept
Here (D=(-5)2-4(1)(3)=13), and (13) is not a perfect square. So the roots are real, irrational and distinct.
Step 2
Why this answer is correct
The correct answer is A. वास्तविक, अपरिमेय और भिन्न / Real, irrational and distinct. Here (D=(-5)2-4(1)(3)=13), and (13) is not a perfect square. So the roots are real, irrational and distinct.
Step 3
Exam Tip
यहाँ (D=(-5)2-4(1)(3)=13) है और (13) पूर्ण वर्ग नहीं है। इसलिए मूल वास्तविक, अपरिमेय और भिन्न हैं।
Here \(\alpha+\beta=2a+1\) and \(\alpha\beta=a^2+a-6\). Since (\(\alpha-\beta\)2=\(\alpha+\beta\)2-4\alpha\beta=25), the positive difference is (5).
Step 2
Why this answer is correct
The correct answer is A. (5). Here \(\alpha+\beta=2a+1\) and \(\alpha\beta=a^2+a-6\). Since (\(\alpha-\beta\)2=\(\alpha+\beta\)2-4\alpha\beta=25), the positive difference is (5).
Step 3
Exam Tip
यहाँ \(\alpha+\beta=2a+1\) और \(\alpha\beta=a^2+a-6\) है। (\(\alpha-\beta\)2=\(\alpha+\beta\)2-4\alpha\beta=25), इसलिए धनात्मक अंतर (5) है।
A. हर वास्तविक (a) के लिए वास्तविक नहीं/Not real for every real (a)
Step 1
Concept
The discriminant is (D=4-4\(a^2+3\)=-4a-2-8). It is negative for every real (a), so the roots are not real.
Step 2
Why this answer is correct
The correct answer is A. हर वास्तविक (a) के लिए वास्तविक नहीं / Not real for every real (a). The discriminant is (D=4-4\(a^2+3\)=-4a-2-8). It is negative for every real (a), so the roots are not real.
Step 3
Exam Tip
विविक्तकर (D=4-4\(a^2+3\)=-4a-2-8) है। यह हर वास्तविक (a) के लिए ऋणात्मक है, इसलिए जड़ें वास्तविक नहीं हैं।
Here \(\alpha+\beta=5\) and \(\alpha\beta=\frac{9}{4}\). Since (\(\alpha-\beta\)2=25-9=16), the positive difference is (4).
Step 2
Why this answer is correct
The correct answer is A. (4). Here \(\alpha+\beta=5\) and \(\alpha\beta=\frac{9}{4}\). Since (\(\alpha-\beta\)2=25-9=16), the positive difference is (4).
Step 3
Exam Tip
\(\alpha+\beta=5\) और \(\alpha\beta=\frac{9}{4}\) है। (\(\alpha-\beta\)2=25-9=16), इसलिए धनात्मक अंतर (4) है।