यदि \(a_n=5\cdot3^{n-1}\) है, तो \(a_5\) का मान क्या होगा?
If \(a_n=5\cdot3^{n-1}\), what is the value of \(a_5\)?
#sequences
#progressions
#geometric-progression
#explicit-rule
A (135)
B (225)
C (405)
D (625)
Explanation opens after your attempt
Step 1
Concept
\(a_5=5\cdot3^4=405\). First find the value of (n-1) in the exponent.
Step 2
Why this answer is correct
The correct answer is C. (405). \(a_5=5\cdot3^4=405\). First find the value of (n-1) in the exponent.
Step 3
Exam Tip
\(a_5=5\cdot3^4=405\)। घात में (n-1) का मान पहले निकालें।
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यदि \(a_n=3\cdot2^{n-1}\) है, तो \(a_6\) का मान क्या होगा?
If \(a_n=3\cdot2^{n-1}\), what is the value of \(a_6\)?
#sequences
#progressions
#geometric-progression
#explicit-rule
A (48)
B (64)
C (96)
D (128)
Explanation opens after your attempt
Step 1
Concept
\(a_6=3\cdot2^5=96\). First find the value of (n-1) in the exponent.
Step 2
Why this answer is correct
The correct answer is C. (96). \(a_6=3\cdot2^5=96\). First find the value of (n-1) in the exponent.
Step 3
Exam Tip
\(a_6=3\cdot2^5=96\)। घात में (n-1) का मान पहले निकालें।
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यदि \(a_n=2\cdot4^{n-1}\) है, तो \(a_5\) का मान क्या होगा?
If \(a_n=2\cdot4^{n-1}\), what is the value of \(a_5\)?
#sequences
#progressions
#geometric-progression
#explicit-rule
A (128)
B (256)
C (512)
D (1024)
Explanation opens after your attempt
Step 1
Concept
\(a_5=2\cdot4^4=512\). First find the value of (n-1) in the exponent.
Step 2
Why this answer is correct
The correct answer is C. (512). \(a_5=2\cdot4^4=512\). First find the value of (n-1) in the exponent.
Step 3
Exam Tip
\(a_5=2\cdot4^4=512\)। घात में (n-1) का मान पहले निकालें।
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यदि किसी अनुक्रम का स्पष्ट नियम \(a_n=pn^2+qn+1\) है और पहले दो पद (6) तथा (15) हैं, तो \(a_4\) का मान क्या होगा?
If the explicit rule of a sequence is \(a_n=pn^2+qn+1\) and the first two terms are (6) and (15), what is the value of \(a_4\)?
#sequences
#progressions
#explicit-rule
#unknown-coefficients
A (41)
B (43)
C (45)
D (47)
Explanation opens after your attempt
Step 1
Concept
From the given terms, (p+q=5) and (2p+q=7), so (p=2), (q=3), and \(a_4=45\). When coefficients are unknown, first form equations using small terms.
Step 2
Why this answer is correct
The correct answer is C. (45). From the given terms, (p+q=5) and (2p+q=7), so (p=2), (q=3), and \(a_4=45\). When coefficients are unknown, first form equations using small terms.
Step 3
Exam Tip
दिए पदों से (p+q=5) और (2p+q=7), इसलिए (p=2), (q=3) और \(a_4=45\)। अज्ञात गुणांक हों तो पहले छोटे पदों से समीकरण बनाएं।
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अनुक्रम \(3,14,59,266,\ldots\) के लिए सही स्पष्ट नियम कौन-सा है?
Which explicit rule is correct for the sequence \(3,14,59,266,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A \(a_n=3n^2\)
B \(a_n=2\cdot5^{n-1}+n^2\)
C \(a_n=5^n-n\)
D \(a_n=n^3+2n\)
Explanation opens after your attempt
Correct Answer
B. \(a_n=2\cdot5^{n-1}+n^2\)
Step 1
Concept
\(2\cdot5^{n-1}+n^2\) gives the given terms. In exams, check both the power and square in rapid growth.
Step 2
Why this answer is correct
The correct answer is B. \(a_n=2\cdot5^{n-1}+n^2\). \(2\cdot5^{n-1}+n^2\) gives the given terms. In exams, check both the power and square in rapid growth.
Step 3
Exam Tip
\(2\cdot5^{n-1}+n^2\) से दिए पद मिलते हैं। परीक्षा में तेज वृद्धि में घात और वर्ग दोनों जाँचें।
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यदि \(a_n=\frac{n(3n+5)}{2}\) है, तो \(a_8\) का मान क्या होगा?
If \(a_n=\frac{n(3n+5)}{2}\), what is the value of \(a_8\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (108)
B (112)
C (116)
D (120)
Explanation opens after your attempt
Step 1
Concept
\(a_8=\frac{8\times29}{2}=116\). In exams, find the bracket value first and simplify.
Step 2
Why this answer is correct
The correct answer is C. (116). \(a_8=\frac{8\times29}{2}=116\). In exams, find the bracket value first and simplify.
Step 3
Exam Tip
\(a_8=\frac{8\times29}{2}=116\) है। परीक्षा में पहले कोष्ठक का मान निकालकर सरल करें।
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अनुक्रम \(8,27,56,95,\ldots\) का सामान्य पद क्या है?
What is the general term of the sequence \(8,27,56,95,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A \(a_n=19n-11\)
B \(a_n=4n^2+4n\)
C \(a_n=5n^2+2n+1\)
D \(a_n=5n^2+4n-1\)
Explanation opens after your attempt
Correct Answer
D. \(a_n=5n^2+4n-1\)
Step 1
Concept
\(5n^2+4n-1\) gives (8,27,56,95). In exams, test the rule on the first four terms.
Step 2
Why this answer is correct
The correct answer is D. \(a_n=5n^2+4n-1\). \(5n^2+4n-1\) gives (8,27,56,95). In exams, test the rule on the first four terms.
Step 3
Exam Tip
\(5n^2+4n-1\) से (8,27,56,95) मिलते हैं। परीक्षा में पहले चार पदों पर नियम जाँचें।
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अनुक्रम \(4,21,52,97,\ldots\) का सामान्य पद क्या है?
What is the general term of the sequence \(4,21,52,97,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A \(a_n=7n^2-4n+1\)
B \(a_n=4n^2\)
C \(a_n=17n-13\)
D \(a_n=5n^2+2n\)
Explanation opens after your attempt
Correct Answer
A. \(a_n=7n^2-4n+1\)
Step 1
Concept
\(7n^2-4n+1\) gives (4,21,52,97). In exams, identify a quadratic rule by equal second differences.
Step 2
Why this answer is correct
The correct answer is A. \(a_n=7n^2-4n+1\). \(7n^2-4n+1\) gives (4,21,52,97). In exams, identify a quadratic rule by equal second differences.
Step 3
Exam Tip
\(7n^2-4n+1\) से (4,21,52,97) मिलते हैं। परीक्षा में दूसरे अंतर समान देखकर वर्गीय नियम पहचानें।
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यदि \(a_n=7n^2-4n+1\) है, तो \(a_5\) का मान क्या होगा?
If \(a_n=7n^2-4n+1\), what is the value of \(a_5\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (150)
B (152)
C (154)
D (156)
Explanation opens after your attempt
Step 1
Concept
\(a_5=175-20+1=156\). In exams, subtract the linear part from the quadratic part.
Step 2
Why this answer is correct
The correct answer is D. (156). \(a_5=175-20+1=156\). In exams, subtract the linear part from the quadratic part.
Step 3
Exam Tip
\(a_5=175-20+1=156\) है। परीक्षा में वर्गीय भाग से रैखिक भाग घटाएँ।
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अनुक्रम \(8,20,42,80,\ldots\) के लिए सही स्पष्ट नियम कौन-सा है?
Which explicit rule is correct for the sequence \(8,20,42,80,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A \(a_n=3\cdot2^n+2n^2\)
B \(a_n=8n\)
C \(a_n=2^n+6n\)
D \(a_n=4n^2+4\)
Explanation opens after your attempt
Correct Answer
A. \(a_n=3\cdot2^n+2n^2\)
Step 1
Concept
\(3\cdot2^n+2n^2\) gives the given terms. In exams, match combined power-and-square rules.
Step 2
Why this answer is correct
The correct answer is A. \(a_n=3\cdot2^n+2n^2\). \(3\cdot2^n+2n^2\) gives the given terms. In exams, match combined power-and-square rules.
Step 3
Exam Tip
\(3\cdot2^n+2n^2\) से दिए पद मिलते हैं। परीक्षा में घात और वर्ग वाले संयुक्त नियम मिलाएँ।
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यदि \(a_n=3\cdot2^n+2n^2\) है, तो \(a_4\) का मान क्या होगा?
If \(a_n=3\cdot2^n+2n^2\), what is the value of \(a_4\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (76)
B (78)
C (80)
D (82)
Explanation opens after your attempt
Step 1
Concept
\(a_4=3\cdot16+2\times16=80\). In exams, add both the power and square parts.
Step 2
Why this answer is correct
The correct answer is C. (80). \(a_4=3\cdot16+2\times16=80\). In exams, add both the power and square parts.
Step 3
Exam Tip
\(a_4=3\cdot16+2\times16=80\) है। परीक्षा में घात और वर्ग दोनों जोड़ें।
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अनुक्रम \(7,25,61,121,\ldots\) का सामान्य पद क्या है?
What is the general term of the sequence \(7,25,61,121,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (a_n=(n+1)3 -n)
B \(a_n=n^3+6\)
C \(a_n=7n\)
D \(a_n=2^n+5n\)
Explanation opens after your attempt
Correct Answer
A. (a_n=(n+1)3 -n)
Step 1
Concept
((n+1)3 -n) gives (7,25,61,121). In exams, check shifted cube rules.
Step 2
Why this answer is correct
The correct answer is A. (a_n=(n+1)3 -n). ((n+1)3 -n) gives (7,25,61,121). In exams, check shifted cube rules.
Step 3
Exam Tip
((n+1)3 -n) से (7,25,61,121) मिलते हैं। परीक्षा में स्थानांतरित घन नियमों को जाँचें।
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यदि (a_n=(n+1)3 -n) है, तो \(a_4\) का मान क्या होगा?
If (a_n=(n+1)3 -n), what is the value of \(a_4\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (117)
B (119)
C (121)
D (123)
Explanation opens after your attempt
Step 1
Concept
\(a_4=5^3-4=121\). In exams, find the power of the bracket first.
Step 2
Why this answer is correct
The correct answer is C. (121). \(a_4=5^3-4=121\). In exams, find the power of the bracket first.
Step 3
Exam Tip
\(a_4=5^3-4=121\) है। परीक्षा में पहले कोष्ठक की घात निकालें।
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अनुक्रम \(2,9,21,38,\ldots\) के लिए सही सामान्य पद कौन-सा है?
Which general term is correct for the sequence \(2,9,21,38,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (a_n=\frac{n(5n-1)}{2})
B (a_n=\frac{n(n+5)}{2})
C \(a_n=7n-5\)
D \(a_n=2n^2\)
Explanation opens after your attempt
Correct Answer
A. (a_n=\frac{n(5n-1)}{2})
Step 1
Concept
(\frac{n(5n-1)}{2}) gives (2,9,21,38). In exams, also check fractional-form general terms.
Step 2
Why this answer is correct
The correct answer is A. (a_n=\frac{n(5n-1)}{2}). (\frac{n(5n-1)}{2}) gives (2,9,21,38). In exams, also check fractional-form general terms.
Step 3
Exam Tip
(\frac{n(5n-1)}{2}) से (2,9,21,38) मिलते हैं। परीक्षा में भिन्न रूप वाले सामान्य पद भी जाँचें।
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यदि \(a_n=\frac{n(5n-1)}{2}\) है, तो \(a_6\) का मान क्या होगा?
If \(a_n=\frac{n(5n-1)}{2}\), what is the value of \(a_6\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (81)
B (83)
C (85)
D (87)
Explanation opens after your attempt
Step 1
Concept
\(a_6=\frac{6\times29}{2}=87\). In exams, find the bracket value first and then divide.
Step 2
Why this answer is correct
The correct answer is D. (87). \(a_6=\frac{6\times29}{2}=87\). In exams, find the bracket value first and then divide.
Step 3
Exam Tip
\(a_6=\frac{6\times29}{2}=87\) है। परीक्षा में पहले कोष्ठक का मान निकालें और फिर भाग दें।
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अनुक्रम \(188,176,164,152,\ldots\) का सामान्य पद क्या है?
What is the general term of the sequence \(188,176,164,152,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A \(a_n=188-12n\)
B \(a_n=200-12n\)
C \(a_n=12n+176\)
D \(a_n=200+n\)
Explanation opens after your attempt
Correct Answer
B. \(a_n=200-12n\)
Step 1
Concept
At (n=1) it gives (188), and at (n=2) it gives (176), so \(a_n=200-12n\). In exams, check the first two terms of a decreasing sequence.
Step 2
Why this answer is correct
The correct answer is B. \(a_n=200-12n\). At (n=1) it gives (188), and at (n=2) it gives (176), so \(a_n=200-12n\). In exams, check the first two terms of a decreasing sequence.
Step 3
Exam Tip
(n=1) पर (188) और (n=2) पर (176) मिलता है, इसलिए \(a_n=200-12n\) है। परीक्षा में घटते अनुक्रम के पहले दो पद जाँचें।
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यदि \(a_n=200-12n\) है, तो \(a_9\) का मान क्या होगा?
If \(a_n=200-12n\), what is the value of \(a_9\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (86)
B (88)
C (90)
D (92)
Explanation opens after your attempt
Step 1
Concept
\(a_9=200-108=92\). In exams, multiply first in a decreasing formula.
Step 2
Why this answer is correct
The correct answer is D. (92). \(a_9=200-108=92\). In exams, multiply first in a decreasing formula.
Step 3
Exam Tip
\(a_9=200-108=92\) है। परीक्षा में घटते सूत्र में गुणन पहले करें।
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अनुक्रम \(12,27,46,69,\ldots\) का सामान्य पद क्या है?
What is the general term of the sequence \(12,27,46,69,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A \(a_n=2n^2+9n+1\)
B \(a_n=12n\)
C \(a_n=15n-3\)
D \(a_n=3n^2+8n\)
Explanation opens after your attempt
Correct Answer
A. \(a_n=2n^2+9n+1\)
Step 1
Concept
\(2n^2+9n+1\) gives (12,27,46,69). In exams, test the quadratic rule with the first four terms.
Step 2
Why this answer is correct
The correct answer is A. \(a_n=2n^2+9n+1\). \(2n^2+9n+1\) gives (12,27,46,69). In exams, test the quadratic rule with the first four terms.
Step 3
Exam Tip
\(2n^2+9n+1\) से (12,27,46,69) मिलते हैं। परीक्षा में वर्गीय नियम को पहले चार पदों से जाँचें।
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यदि \(a_n=2n^2+9n+1\) है, तो \(a_5\) का मान क्या होगा?
If \(a_n=2n^2+9n+1\), what is the value of \(a_5\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (92)
B (94)
C (96)
D (98)
Explanation opens after your attempt
Step 1
Concept
\(a_5=50+45+1=96\). In exams, add both the square and linear parts.
Step 2
Why this answer is correct
The correct answer is C. (96). \(a_5=50+45+1=96\). In exams, add both the square and linear parts.
Step 3
Exam Tip
\(a_5=50+45+1=96\) है। परीक्षा में वर्ग और रैखिक भाग दोनों जोड़ें।
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अनुक्रम \(2,15,64,257,\ldots\) के लिए सही स्पष्ट नियम कौन-सा है?
Which explicit rule is correct for the sequence \(2,15,64,257,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A \(a_n=4^n+n-3\)
B \(a_n=4n-2\)
C \(a_n=2^n+4n\)
D \(a_n=n^4+1\)
Explanation opens after your attempt
Correct Answer
A. \(a_n=4^n+n-3\)
Step 1
Concept
\(4^n+n-3\) gives (2,15,64,257). In exams, check a power rule in rapid growth.
Step 2
Why this answer is correct
The correct answer is A. \(a_n=4^n+n-3\). \(4^n+n-3\) gives (2,15,64,257). In exams, check a power rule in rapid growth.
Step 3
Exam Tip
\(4^n+n-3\) से (2,15,64,257) मिलते हैं। परीक्षा में तेज वृद्धि में घात वाला नियम जाँचें।
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यदि \(a_n=4^n+n-3\) है, तो \(a_4\) का मान क्या होगा?
If \(a_n=4^n+n-3\), what is the value of \(a_4\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (253)
B (255)
C (257)
D (259)
Explanation opens after your attempt
Step 1
Concept
\(a_4=256+4-3=257\). In exams, add the full linear part after the power.
Step 2
Why this answer is correct
The correct answer is C. (257). \(a_4=256+4-3=257\). In exams, add the full linear part after the power.
Step 3
Exam Tip
\(a_4=256+4-3=257\) है। परीक्षा में घात के बाद पूरा रैखिक भाग जोड़ें।
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अनुक्रम \(0,12,72,240,\ldots\) का सामान्य पद क्या है?
What is the general term of the sequence \(0,12,72,240,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A \(a_n=n^4-n^2\)
B \(a_n=n^3+n\)
C \(a_n=12n\)
D \(a_n=2n^4\)
Explanation opens after your attempt
Correct Answer
A. \(a_n=n^4-n^2\)
Step 1
Concept
\(n^4-n^2\) gives (0,12,72,240). In exams, test higher-power options with small (n).
Step 2
Why this answer is correct
The correct answer is A. \(a_n=n^4-n^2\). \(n^4-n^2\) gives (0,12,72,240). In exams, test higher-power options with small (n).
Step 3
Exam Tip
\(n^4-n^2\) से (0,12,72,240) मिलते हैं। परीक्षा में उच्च घात वाले विकल्पों को छोटे (n) से जाँचें।
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यदि \(a_n=n^4-n^2\) है, तो \(a_3\) का मान क्या होगा?
If \(a_n=n^4-n^2\), what is the value of \(a_3\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (68)
B (70)
C (72)
D (74)
Explanation opens after your attempt
Step 1
Concept
\(a_3=81-9=72\). In exams, calculate the fourth power and square separately.
Step 2
Why this answer is correct
The correct answer is C. (72). \(a_3=81-9=72\). In exams, calculate the fourth power and square separately.
Step 3
Exam Tip
\(a_3=81-9=72\) है। परीक्षा में चौथी घात और वर्ग अलग-अलग निकालें।
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अनुक्रम \(3,16,29,42,\ldots\) में (159) कौन-सा पद है?
In the sequence \(3,16,29,42,\ldots\), which term is (159)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A बारहवाँ पद / (12)th term
B तेरहवाँ पद / (13)th term
C चौदहवाँ पद / (14)th term
D पंद्रहवाँ पद / (15)th term
Explanation opens after your attempt
Correct Answer
B. तेरहवाँ पद / (13)th term
Step 1
Concept
Its rule is \(a_n=13n-10\), and (13n-10=159) gives (n=13). In exams, equate the given term to the general term.
Step 2
Why this answer is correct
The correct answer is B. तेरहवाँ पद / (13)th term. Its rule is \(a_n=13n-10\), and (13n-10=159) gives (n=13). In exams, equate the given term to the general term.
Step 3
Exam Tip
इसका नियम \(a_n=13n-10\) है और (13n-10=159) से (n=13) है। परीक्षा में दिए पद को सामान्य पद के बराबर रखें।
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यदि \(a_n=13n-10\) है, तो पहले पाँच पदों का औसत क्या होगा?
If \(a_n=13n-10\), what is the average of the first five terms?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (29)
B (31)
C (33)
D (35)
Explanation opens after your attempt
Step 1
Concept
The first five terms are (3,16,29,42,55), and the average is (29). In exams, divide the sum by the number of terms.
Step 2
Why this answer is correct
The correct answer is A. (29). The first five terms are (3,16,29,42,55), and the average is (29). In exams, divide the sum by the number of terms.
Step 3
Exam Tip
पहले पाँच पद (3,16,29,42,55) हैं और औसत (29) है। परीक्षा में औसत के लिए योग को पदों की संख्या से भाग दें।
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अनुक्रम \(2,23,124,625,\ldots\) के लिए सही सामान्य पद कौन-सा है?
Which general term is correct for the sequence \(2,23,124,625,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A \(a_n=5^n+n-4\)
B \(a_n=5n-3\)
C \(a_n=2^n+5\)
D \(a_n=n^5-4\)
Explanation opens after your attempt
Correct Answer
A. \(a_n=5^n+n-4\)
Step 1
Concept
\(5^n+n-4\) gives (2,23,124,625). In exams, also check the small linear part in a power rule.
Step 2
Why this answer is correct
The correct answer is A. \(a_n=5^n+n-4\). \(5^n+n-4\) gives (2,23,124,625). In exams, also check the small linear part in a power rule.
Step 3
Exam Tip
\(5^n+n-4\) से (2,23,124,625) मिलते हैं। परीक्षा में घात वाले नियम में छोटा रैखिक भाग भी जाँचें।
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यदि \(a_n=5^n+n-4\) है, तो \(a_3\) का मान क्या होगा?
If \(a_n=5^n+n-4\), what is the value of \(a_3\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (120)
B (122)
C (124)
D (126)
Explanation opens after your attempt
Step 1
Concept
\(a_3=125+3-4=124\). In exams, keep both the power and linear part correct.
Step 2
Why this answer is correct
The correct answer is C. (124). \(a_3=125+3-4=124\). In exams, keep both the power and linear part correct.
Step 3
Exam Tip
\(a_3=125+3-4=124\) है। परीक्षा में घात और रैखिक भाग दोनों सही रखें।
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अनुक्रम \(9,26,55,96,\ldots\) का सामान्य पद क्या है?
What is the general term of the sequence \(9,26,55,96,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A \(a_n=6n^2-n+4\)
B \(a_n=9n\)
C \(a_n=17n-8\)
D \(a_n=5n^2+4n\)
Explanation opens after your attempt
Correct Answer
A. \(a_n=6n^2-n+4\)
Step 1
Concept
\(6n^2-n+4\) gives (9,26,55,96). In exams, check a quadratic rule when second differences are constant.
Step 2
Why this answer is correct
The correct answer is A. \(a_n=6n^2-n+4\). \(6n^2-n+4\) gives (9,26,55,96). In exams, check a quadratic rule when second differences are constant.
Step 3
Exam Tip
\(6n^2-n+4\) से (9,26,55,96) मिलते हैं। परीक्षा में दूसरे अंतर समान हों तो वर्गीय नियम देखें।
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यदि \(a_n=6n^2-n+4\) है, तो \(a_4:a_2\) क्या होगा?
If \(a_n=6n^2-n+4\), what is \(a_4:a_2\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A (96:26)
B (48:13)
C (13:48)
D (46:13)
Explanation opens after your attempt
Correct Answer
B. (48:13)
Step 1
Concept
\(a_4=96\) and \(a_2=26\), so the simplified ratio is (48:13). In exams, do not forget to simplify the ratio.
Step 2
Why this answer is correct
The correct answer is B. (48:13). \(a_4=96\) and \(a_2=26\), so the simplified ratio is (48:13). In exams, do not forget to simplify the ratio.
Step 3
Exam Tip
\(a_4=96\) और \(a_2=26\), इसलिए सरल अनुपात (48:13) है। परीक्षा में अनुपात सरल करना न भूलें।
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अनुक्रम \(2,\frac{11}{2},\frac{21}{2},17,\ldots\) के लिए सही स्पष्ट नियम कौन-सा है?
Which explicit rule is correct for the sequence \(2,\frac{11}{2},\frac{21}{2},17,\ldots\)?
#sequences
#progressions
#explicit-rule
#class-9
#expert
A \(a_n=\frac{3n^2+5n}{4}\)
B (a_n=\frac{n(n+3)}{2})
C \(a_n=3n-1\)
D \(a_n=\frac{5n^2+n}{4}\)
Explanation opens after your attempt
Correct Answer
A. \(a_n=\frac{3n^2+5n}{4}\)
Step 1
Concept
\(\frac{3n^2+5n}{4}\) gives the given terms. In exams, match fractional terms with options too.
Step 2
Why this answer is correct
The correct answer is A. \(a_n=\frac{3n^2+5n}{4}\). \(\frac{3n^2+5n}{4}\) gives the given terms. In exams, match fractional terms with options too.
Step 3
Exam Tip
\(\frac{3n^2+5n}{4}\) से दिए पद मिलते हैं। परीक्षा में भिन्न पदों को भी विकल्पों से मिलाएँ।
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