Here (\left\(2x^{-3}\right\)^{-2}=2^{-2}x^{6}=\frac{x^{6}}{4}), so multiplying by \(x^{-1}\) gives \(\frac{x^{5}}{4}\). In exams, first convert negative exponents carefully.
Step 2
Why this answer is correct
The correct answer is A. \(\frac{x^{5}}{4}\). Here (\left\(2x^{-3}\right\)^{-2}=2^{-2}x^{6}=\frac{x^{6}}{4}), so multiplying by \(x^{-1}\) gives \(\frac{x^{5}}{4}\). In exams, first convert negative exponents carefully.
Step 3
Exam Tip
(\left\(2x^{-3}\right\)^{-2}=2^{-2}x^{6}=\frac{x^{6}}{4}), इसलिए \(x^{-1}\) से गुणा करने पर \(\frac{x^{5}}{4}\) मिलता है। परीक्षा में ऋणात्मक घात को पहले धनात्मक रूप में बदलें।
The numerator exponent is ((m+2)+(3-m)=5), and \(\frac{a^{5}}{a^{4}}=a\). In exams, add and subtract exponents only for the same base.
Step 2
Why this answer is correct
The correct answer is A. (a). The numerator exponent is ((m+2)+(3-m)=5), and \(\frac{a^{5}}{a^{4}}=a\). In exams, add and subtract exponents only for the same base.
Step 3
Exam Tip
ऊपर की घातें ((m+2)+(3-m)=5) हैं और \(\frac{a^{5}}{a^{4}}=a\)। परीक्षा में समान आधार की घातों को जोड़ना और घटाना याद रखें।
We have (\left\(3^{x}\right\)^{2}=3^{2x}) and \(729=3^{6}\), so (2x=6) and (x=3). In exams, rewrite both sides with the same base.
Step 2
Why this answer is correct
The correct answer is B. (3). We have (\left\(3^{x}\right\)^{2}=3^{2x}) and \(729=3^{6}\), so (2x=6) and (x=3). In exams, rewrite both sides with the same base.
Step 3
Exam Tip
(\left\(3^{x}\right\)^{2}=3^{2x}) और \(729=3^{6}\), इसलिए (2x=6) और (x=3)। परीक्षा में दोनों पक्षों को समान आधार में लिखें।
Since \(25^{-2}=5^{-4}\) and \(125=5^{3}\), \(\frac{5^{8}\cdot5^{-4}}{5^{3}}=5^{1}=5\). In exams, convert (25) and (125) into powers of (5).
Step 2
Why this answer is correct
The correct answer is B. (5). Since \(25^{-2}=5^{-4}\) and \(125=5^{3}\), \(\frac{5^{8}\cdot5^{-4}}{5^{3}}=5^{1}=5\). In exams, convert (25) and (125) into powers of (5).
Step 3
Exam Tip
\(25^{-2}=5^{-4}\) और \(125=5^{3}\), इसलिए \(\frac{5^{8}\cdot5^{-4}}{5^{3}}=5^{1}=5\)। परीक्षा में (25) और (125) को (5) की घात में बदलें।
To rationalize, \(\frac{1}{2-\sqrt{3}}\cdot\frac{2+\sqrt{3}}{2+\sqrt{3}}=\frac{2+\sqrt{3}}{4-3}=2+\sqrt{3}\). In exams, multiply by the conjugate.
Step 2
Why this answer is correct
The correct answer is A. \(2+\sqrt{3}\). To rationalize, \(\frac{1}{2-\sqrt{3}}\cdot\frac{2+\sqrt{3}}{2+\sqrt{3}}=\frac{2+\sqrt{3}}{4-3}=2+\sqrt{3}\). In exams, multiply by the conjugate.
Step 3
Exam Tip
हर को परिमेय बनाने के लिए \(\frac{1}{2-\sqrt{3}}\cdot\frac{2+\sqrt{3}}{2+\sqrt{3}}=\frac{2+\sqrt{3}}{4-3}=2+\sqrt{3}\)। परीक्षा में संयुग्म से गुणा करें।
Here \(x=\frac{8}{9}\), so \(x^{-1}=\frac{9}{8}\). In exams, apply \(a^{-n}=\frac{1}{a^{n}}\) in the correct direction.
Step 2
Why this answer is correct
The correct answer is A. \(\frac{9}{8}\). Here \(x=\frac{8}{9}\), so \(x^{-1}=\frac{9}{8}\). In exams, apply \(a^{-n}=\frac{1}{a^{n}}\) in the correct direction.
Step 3
Exam Tip
\(x=\frac{8}{9}\), इसलिए \(x^{-1}=\frac{9}{8}\)। परीक्षा में \(a^{-n}=\frac{1}{a^{n}}\) को सही दिशा में लगाएं।
Inside, \(\frac{4x^{2}y^{-3}}{2x^{-1}y}=2x^{3}y^{-4}\), and raising to (-2) gives \(\frac{y^{8}}{4x^{6}}\). In exams, simplify inside the bracket first.
Step 2
Why this answer is correct
The correct answer is A. \(\frac{y^{8}}{4x^{6}}\). Inside, \(\frac{4x^{2}y^{-3}}{2x^{-1}y}=2x^{3}y^{-4}\), and raising to (-2) gives \(\frac{y^{8}}{4x^{6}}\). In exams, simplify inside the bracket first.
Step 3
Exam Tip
अंदर \(\frac{4x^{2}y^{-3}}{2x^{-1}y}=2x^{3}y^{-4}\), इसलिए घात (-2) देने पर \(\frac{y^{8}}{4x^{6}}\) मिलता है। परीक्षा में पहले कोष्ठक के अंदर सरल करें।
Here \(2^{x+1}+2^{x}=2\cdot2^{x}+2^{x}=3\cdot2^{x}=48\), so \(2^{x}=16=2^{4}\). In exams, factor the common power \(2^{x}\).
Step 2
Why this answer is correct
The correct answer is B. (4). Here \(2^{x+1}+2^{x}=2\cdot2^{x}+2^{x}=3\cdot2^{x}=48\), so \(2^{x}=16=2^{4}\). In exams, factor the common power \(2^{x}\).
Step 3
Exam Tip
\(2^{x+1}+2^{x}=2\cdot2^{x}+2^{x}=3\cdot2^{x}=48\), इसलिए \(2^{x}=16=2^{4}\)। परीक्षा में सामान्य घात \(2^{x}\) बाहर लें।
We get \(\sqrt{50}=5\sqrt{2}\), \(\sqrt{18}=3\sqrt{2}\), and \(\sqrt{8}=2\sqrt{2}\), so the result is \(6\sqrt{2}\). In exams, combine only like surd terms.
Step 2
Why this answer is correct
The correct answer is A. \(6\sqrt{2}\). We get \(\sqrt{50}=5\sqrt{2}\), \(\sqrt{18}=3\sqrt{2}\), and \(\sqrt{8}=2\sqrt{2}\), so the result is \(6\sqrt{2}\). In exams, combine only like surd terms.
Step 3
Exam Tip
\(\sqrt{50}=5\sqrt{2}\), \(\sqrt{18}=3\sqrt{2}\), और \(\sqrt{8}=2\sqrt{2}\), इसलिए परिणाम \(6\sqrt{2}\) है। परीक्षा में समान करणी पदों को ही जोड़ें।
Since (\left\(\frac{27}{8}\right\)^{\frac{1}{3}}=\frac{3}{2}), (\left\(\frac{27}{8}\right\)^{-\frac{2}{3}}=\left\(\frac{3}{2}\right\)^{-2}=\frac{4}{9}). In exams, take the cube root first.
Step 2
Why this answer is correct
The correct answer is A. \(\frac{4}{9}\). Since (\left\(\frac{27}{8}\right\)^{\frac{1}{3}}=\frac{3}{2}), (\left\(\frac{27}{8}\right\)^{-\frac{2}{3}}=\left\(\frac{3}{2}\right\)^{-2}=\frac{4}{9}). In exams, take the cube root first.
Step 3
Exam Tip
(\left\(\frac{27}{8}\right\)^{\frac{1}{3}}=\frac{3}{2}), इसलिए (\left\(\frac{27}{8}\right\)^{-\frac{2}{3}}=\left\(\frac{3}{2}\right\)^{-2}=\frac{4}{9})। परीक्षा में पहले घनमूल निकालें।
Rationalizing gives \(\frac{1}{\sqrt{5}+2}\cdot\frac{\sqrt{5}-2}{\sqrt{5}-2}=\frac{\sqrt{5}-2}{5-4}=\sqrt{5}-2\). In exams, use the conjugate of the denominator.
Step 2
Why this answer is correct
The correct answer is A. \(\sqrt{5}-2\). Rationalizing gives \(\frac{1}{\sqrt{5}+2}\cdot\frac{\sqrt{5}-2}{\sqrt{5}-2}=\frac{\sqrt{5}-2}{5-4}=\sqrt{5}-2\). In exams, use the conjugate of the denominator.
Step 3
Exam Tip
\(\frac{1}{\sqrt{5}+2}\cdot\frac{\sqrt{5}-2}{\sqrt{5}-2}=\frac{\sqrt{5}-2}{5-4}=\sqrt{5}-2\)। परीक्षा में हर के संयुग्म का प्रयोग करें।
Here (\left\(9^{2}\right\)^{3}=\(3^{2}\)^{6}=3^{12}), and \(3^{12}\div3^{10}=3^{2}\). In exams, write (9) as \(3^{2}\).
Step 2
Why this answer is correct
The correct answer is B. \(3^{2}\). Here (\left\(9^{2}\right\)^{3}=\(3^{2}\)^{6}=3^{12}), and \(3^{12}\div3^{10}=3^{2}\). In exams, write (9) as \(3^{2}\).
Step 3
Exam Tip
(\left\(9^{2}\right\)^{3}=\(3^{2}\)^{6}=3^{12}), और \(3^{12}\div3^{10}=3^{2}\)। परीक्षा में (9) को \(3^{2}\) लिखें।
We have (\left\(ab^{-2}\right\)^{3}=a^{3}b^{-6}), and multiplying by \(a^{-1}b^{5}\) gives \(a^{2}b^{-1}\). In exams, add exponents separately for each variable.
Step 2
Why this answer is correct
The correct answer is A. \(a^{2}b^{-1}\). We have (\left\(ab^{-2}\right\)^{3}=a^{3}b^{-6}), and multiplying by \(a^{-1}b^{5}\) gives \(a^{2}b^{-1}\). In exams, add exponents separately for each variable.
Step 3
Exam Tip
(\left\(ab^{-2}\right\)^{3}=a^{3}b^{-6}), फिर \(a^{-1}b^{5}\) से गुणा करने पर \(a^{2}b^{-1}\) मिलता है। परीक्षा में हर चर की घात अलग-अलग जोड़ें।
Using (x^{2}-y^{2}=(x-y)(x+y)), we get \(x-y=2\sqrt{2}\) and (x+y=6), so the value is \(12\sqrt{2}\). In exams, identities reduce calculation.
Step 2
Why this answer is correct
The correct answer is A. \(12\sqrt{2}\). Using (x^{2}-y^{2}=(x-y)(x+y)), we get \(x-y=2\sqrt{2}\) and (x+y=6), so the value is \(12\sqrt{2}\). In exams, identities reduce calculation.
Step 3
Exam Tip
(x^{2}-y^{2}=(x-y)(x+y)), जहाँ \(x-y=2\sqrt{2}\) और (x+y=6), इसलिए मान \(12\sqrt{2}\) है। परीक्षा में पहचान से लंबी गणना बचती है।
Here (\(2^{5}\)^{3}=2^{15}), \(4^{-2}=2^{-4}\), and \(8^{2}=2^{6}\), so the net exponent is (15-4-6=5). In exams, convert all bases to (2).
Step 2
Why this answer is correct
The correct answer is A. \(2^{5}\). Here (\(2^{5}\)^{3}=2^{15}), \(4^{-2}=2^{-4}\), and \(8^{2}=2^{6}\), so the net exponent is (15-4-6=5). In exams, convert all bases to (2).
Step 3
Exam Tip
(\(2^{5}\)^{3}=2^{15}), \(4^{-2}=2^{-4}\), और \(8^{2}=2^{6}\), इसलिए कुल घात (15-4-6=5) है। परीक्षा में सभी आधार (2) में बदलें।
Since \(\sqrt{x^{3}}=x^{\frac{3}{2}}\), \(x^{\frac{3}{2}}\cdot x^{-\frac{1}{2}}=x^{1}=x\). In exams, convert radicals to fractional exponents.
Step 2
Why this answer is correct
The correct answer is A. (x). Since \(\sqrt{x^{3}}=x^{\frac{3}{2}}\), \(x^{\frac{3}{2}}\cdot x^{-\frac{1}{2}}=x^{1}=x\). In exams, convert radicals to fractional exponents.
Step 3
Exam Tip
\(\sqrt{x^{3}}=x^{\frac{3}{2}}\), इसलिए \(x^{\frac{3}{2}}\cdot x^{-\frac{1}{2}}=x^{1}=x\)। परीक्षा में मूल को भिन्न घात में बदलें।
Inside, \(\frac{x^{-2}y^{3}}{x^{4}y^{-1}}=x^{-6}y^{4}\), and raising to (-1) gives \(x^{6}y^{-4}\). In exams, subtract exponents during division.
Step 2
Why this answer is correct
The correct answer is A. \(x^{6}y^{-4}\). Inside, \(\frac{x^{-2}y^{3}}{x^{4}y^{-1}}=x^{-6}y^{4}\), and raising to (-1) gives \(x^{6}y^{-4}\). In exams, subtract exponents during division.
Step 3
Exam Tip
अंदर \(\frac{x^{-2}y^{3}}{x^{4}y^{-1}}=x^{-6}y^{4}\), और (-1) घात लेने पर \(x^{6}y^{-4}\) मिलता है। परीक्षा में भाग में घात घटती है।
Here \(\frac{1}{a}=2-\sqrt{3}\), so \(a+\frac{1}{a}=4\) and \(a^{2}+\frac{1}{a^{2}}=4^{2}-2=14\). In exams, use the identity (\left\(a+\frac{1}{a}\right\)^{2}).
Step 2
Why this answer is correct
The correct answer is A. (14). Here \(\frac{1}{a}=2-\sqrt{3}\), so \(a+\frac{1}{a}=4\) and \(a^{2}+\frac{1}{a^{2}}=4^{2}-2=14\). In exams, use the identity (\left\(a+\frac{1}{a}\right\)^{2}).
Step 3
Exam Tip
\(\frac{1}{a}=2-\sqrt{3}\), इसलिए \(a+\frac{1}{a}=4\) और \(a^{2}+\frac{1}{a^{2}}=4^{2}-2=14\)। परीक्षा में (\left\(a+\frac{1}{a}\right\)^{2}) पहचान लगाएं।
The first product is (7-5=2), and \(\sqrt{20}=2\sqrt{5}\), so the answer is \(2+2\sqrt{5}\). In exams, identify the conjugate product first.
Step 2
Why this answer is correct
The correct answer is A. \(2+2\sqrt{5}\). The first product is (7-5=2), and \(\sqrt{20}=2\sqrt{5}\), so the answer is \(2+2\sqrt{5}\). In exams, identify the conjugate product first.
Step 3
Exam Tip
पहला गुणनफल (7-5=2) है और \(\sqrt{20}=2\sqrt{5}\), इसलिए उत्तर \(2+2\sqrt{5}\) है। परीक्षा में पहले संयुग्म गुणनफल पहचानें।
Since \(125=5^{3}\), (x=3), and since \(32=2^{5}\), (y=5), so (x+y=8). In exams, write numbers as powers of their prime bases.
Step 2
Why this answer is correct
The correct answer is C. (8). Since \(125=5^{3}\), (x=3), and since \(32=2^{5}\), (y=5), so (x+y=8). In exams, write numbers as powers of their prime bases.
Step 3
Exam Tip
\(125=5^{3}\) से (x=3) और \(32=2^{5}\) से (y=5), इसलिए (x+y=8)। परीक्षा में संख्याओं को उनके मूल आधार की घात में लिखें।
Here \(3^{-2}+3^{-1}=\frac{1}{9}+\frac{1}{3}=\frac{4}{9}\), and \(3^{-3}=\frac{1}{27}\), so the value is (12). In exams, convert negative powers into fractions.
Step 2
Why this answer is correct
The correct answer is A. (12). Here \(3^{-2}+3^{-1}=\frac{1}{9}+\frac{1}{3}=\frac{4}{9}\), and \(3^{-3}=\frac{1}{27}\), so the value is (12). In exams, convert negative powers into fractions.
Step 3
Exam Tip
\(3^{-2}+3^{-1}=\frac{1}{9}+\frac{1}{3}=\frac{4}{9}\), और \(3^{-3}=\frac{1}{27}\), इसलिए मान (12) है। परीक्षा में ऋणात्मक घातों को भिन्न में बदलें।
(\(\sqrt{6}+\sqrt{2}\)^{2}=6+2+2\sqrt{12}=8+4\sqrt{3}). In exams, do not miss the middle term of ((a+b)^{2}).
Step 2
Why this answer is correct
The correct answer is A. \(8+4\sqrt{3}\). (\(\sqrt{6}+\sqrt{2}\)^{2}=6+2+2\sqrt{12}=8+4\sqrt{3}). In exams, do not miss the middle term of ((a+b)^{2}).
Step 3
Exam Tip
(\(\sqrt{6}+\sqrt{2}\)^{2}=6+2+2\sqrt{12}=8+4\sqrt{3})। परीक्षा में ((a+b)^{2}) का मध्य पद न भूलें।
Inside, \(a^{3-(-1)}b^{-2-2}=a^{4}b^{-4}\), and squaring gives \(a^{8}b^{-8}\). In exams, watch the sign when subtracting negative exponents.
Step 2
Why this answer is correct
The correct answer is A. \(a^{8}b^{-8}\). Inside, \(a^{3-(-1)}b^{-2-2}=a^{4}b^{-4}\), and squaring gives \(a^{8}b^{-8}\). In exams, watch the sign when subtracting negative exponents.
Step 3
Exam Tip
अंदर \(a^{3-(-1)}b^{-2-2}=a^{4}b^{-4}\), इसलिए वर्ग करने पर \(a^{8}b^{-8}\) है। परीक्षा में ऋणात्मक घात घटाते समय चिह्न पर ध्यान दें।
Since \(\frac{1}{2-\sqrt{3}}=2+\sqrt{3}\), (\frac{1}{x}+x=\(2+\sqrt{3}\)+\(2-\sqrt{3}\)=4). In exams, identify conjugate numbers quickly.
Step 2
Why this answer is correct
The correct answer is A. (4). Since \(\frac{1}{2-\sqrt{3}}=2+\sqrt{3}\), (\frac{1}{x}+x=\(2+\sqrt{3}\)+\(2-\sqrt{3}\)=4). In exams, identify conjugate numbers quickly.
Step 3
Exam Tip
\(\frac{1}{2-\sqrt{3}}=2+\sqrt{3}\), इसलिए (\frac{1}{x}+x=\(2+\sqrt{3}\)+\(2-\sqrt{3}\)=4)। परीक्षा में संयुग्म संख्या तुरंत पहचानें।
Since \(6^{5}=2^{5}\cdot3^{5}\), \(\frac{2^{5}3^{5}}{2^{3}3^{4}}=2^{2}\cdot3\). In exams, split a composite base into prime bases.
Step 2
Why this answer is correct
The correct answer is A. \(2^{2}\cdot3\). Since \(6^{5}=2^{5}\cdot3^{5}\), \(\frac{2^{5}3^{5}}{2^{3}3^{4}}=2^{2}\cdot3\). In exams, split a composite base into prime bases.
Step 3
Exam Tip
\(6^{5}=2^{5}\cdot3^{5}\), इसलिए \(\frac{2^{5}3^{5}}{2^{3}3^{4}}=2^{2}\cdot3\)। परीक्षा में मिश्रित आधार को अभाज्य आधारों में तोड़ें।
The left side has exponents (2n) and (3n), so (2n=8) and (3n=12), giving (n=4). In exams, match exponents of both variables.
Step 2
Why this answer is correct
The correct answer is C. (4). The left side has exponents (2n) and (3n), so (2n=8) and (3n=12), giving (n=4). In exams, match exponents of both variables.
Step 3
Exam Tip
बाएँ पक्ष में घातें (2n) और (3n) हैं, इसलिए (2n=8) और (3n=12) से (n=4)। परीक्षा में दोनों चर की घात मिलाकर जांचें।
Since \(\sqrt[3]{64}=4\) and \(\sqrt[3]{x^{6}}=x^{2}\), the answer is \(4x^{2}\). In exams, divide the exponent by (3) for cube roots.
Step 2
Why this answer is correct
The correct answer is A. \(4x^{2}\). Since \(\sqrt[3]{64}=4\) and \(\sqrt[3]{x^{6}}=x^{2}\), the answer is \(4x^{2}\). In exams, divide the exponent by (3) for cube roots.
Step 3
Exam Tip
\(\sqrt[3]{64}=4\) और \(\sqrt[3]{x^{6}}=x^{2}\), इसलिए उत्तर \(4x^{2}\) है। परीक्षा में घनमूल में घात को (3) से भाग दें।
(\(\sqrt{11}-\sqrt{2}\)^{2}=11+2-2\sqrt{22}=13-2\sqrt{22}). In exams, include both \(+b^{2}\) and (-2ab) in ((a-b)^{2}).
Step 2
Why this answer is correct
The correct answer is A. \(13-2\sqrt{22}\). (\(\sqrt{11}-\sqrt{2}\)^{2}=11+2-2\sqrt{22}=13-2\sqrt{22}). In exams, include both \(+b^{2}\) and (-2ab) in ((a-b)^{2}).
Step 3
Exam Tip
(\(\sqrt{11}-\sqrt{2}\)^{2}=11+2-2\sqrt{22}=13-2\sqrt{22})। परीक्षा में ((a-b)^{2}) में \(+b^{2}\) और (-2ab) दोनों लिखें।
From \(2^{a}=2^{3}\), (a=3), and from \(3^{b}=3^{4}\), (b=4), so \(a^{b}=3^{4}=81\). In exams, compare powers using equal bases.
Step 2
Why this answer is correct
The correct answer is C. (81). From \(2^{a}=2^{3}\), (a=3), and from \(3^{b}=3^{4}\), (b=4), so \(a^{b}=3^{4}=81\). In exams, compare powers using equal bases.
Step 3
Exam Tip
\(2^{a}=2^{3}\) से (a=3) और \(3^{b}=3^{4}\) से (b=4), इसलिए \(a^{b}=3^{4}=81\)। परीक्षा में घातों की तुलना समान आधार पर करें।
Here (16^{-\frac{3}{4}}=\(2^{4}\)^{-\frac{3}{4}}=2^{-3}) and (8^{\frac{2}{3}}=\(2^{3}\)^{\frac{2}{3}}=2^{2}), so the value is \(2^{-1}=\frac{1}{2}\). In exams, multiply powers of powers.
Step 2
Why this answer is correct
The correct answer is A. \(\frac{1}{2}\). Here (16^{-\frac{3}{4}}=\(2^{4}\)^{-\frac{3}{4}}=2^{-3}) and (8^{\frac{2}{3}}=\(2^{3}\)^{\frac{2}{3}}=2^{2}), so the value is \(2^{-1}=\frac{1}{2}\). In exams, multiply powers of powers.
Step 3
Exam Tip
(16^{-\frac{3}{4}}=\(2^{4}\)^{-\frac{3}{4}}=2^{-3}) और (8^{\frac{2}{3}}=\(2^{3}\)^{\frac{2}{3}}=2^{2}), इसलिए मान \(2^{-1}=\frac{1}{2}\) है। परीक्षा में घात के ऊपर घात को गुणा करें।
Since (\(2+\sqrt{3}\)^{2}=4+3+4\sqrt{3}=7+4\sqrt{3}), \(\sqrt{A}=2+\sqrt{3}\). In exams, recognize the form ((a+b)^{2}).
Step 2
Why this answer is correct
The correct answer is A. \(2+\sqrt{3}\). Since (\(2+\sqrt{3}\)^{2}=4+3+4\sqrt{3}=7+4\sqrt{3}), \(\sqrt{A}=2+\sqrt{3}\). In exams, recognize the form ((a+b)^{2}).
Step 3
Exam Tip
(\(2+\sqrt{3}\)^{2}=4+3+4\sqrt{3}=7+4\sqrt{3}), इसलिए \(\sqrt{A}=2+\sqrt{3}\)। परीक्षा में रूप ((a+b)^{2}) पहचानें।
Here \(x^{-1}+y^{-1}=\frac{x+y}{xy}\) and ((xy)^{-1}=\frac{1}{xy}), so division gives (x+y). In exams, converting negative exponents to fractions is safer.
Step 2
Why this answer is correct
The correct answer is A. (x+y). Here \(x^{-1}+y^{-1}=\frac{x+y}{xy}\) and ((xy)^{-1}=\frac{1}{xy}), so division gives (x+y). In exams, converting negative exponents to fractions is safer.
Step 3
Exam Tip
\(x^{-1}+y^{-1}=\frac{x+y}{xy}\) और ((xy)^{-1}=\frac{1}{xy}), इसलिए भाग करने पर (x+y) मिलता है। परीक्षा में ऋणात्मक घात को भिन्न में बदलना सुरक्षित तरीका है।
\(\frac{3x^{-2}}{y^{-1}}=3x^{-2}y\), its cube is \(27x^{-6}y^{3}\), and multiplying by \(\frac{y^{2}}{27}\) gives \(x^{-6}y^{5}\). In exams, turn division by a negative power into multiplication.
Step 2
Why this answer is correct
The correct answer is A. \(x^{-6}y^{5}\). \(\frac{3x^{-2}}{y^{-1}}=3x^{-2}y\), its cube is \(27x^{-6}y^{3}\), and multiplying by \(\frac{y^{2}}{27}\) gives \(x^{-6}y^{5}\). In exams, turn division by a negative power into multiplication.
Step 3
Exam Tip
\(\frac{3x^{-2}}{y^{-1}}=3x^{-2}y\), इसका घन \(27x^{-6}y^{3}\) है, फिर \(\frac{y^{2}}{27}\) से गुणा करने पर \(x^{-6}y^{5}\) मिलता है। परीक्षा में भाग को ऋणात्मक घात से गुणा में बदलें।
\(\sqrt{45}=3\sqrt{5}\) and \(\sqrt{20}=2\sqrt{5}\), so the numerator is \(\sqrt{5}\), and division gives (1). In exams, first make like radicals.
Step 2
Why this answer is correct
The correct answer is A. (1). \(\sqrt{45}=3\sqrt{5}\) and \(\sqrt{20}=2\sqrt{5}\), so the numerator is \(\sqrt{5}\), and division gives (1). In exams, first make like radicals.
Step 3
Exam Tip
\(\sqrt{45}=3\sqrt{5}\) और \(\sqrt{20}=2\sqrt{5}\), इसलिए ऊपर \(\sqrt{5}\) है और भाग देने पर (1) मिलता है। परीक्षा में पहले समान करणी बनाएं।
(\(\sqrt{3}-\sqrt{2}\)^{2}=3+2-2\sqrt{6}=5-2\sqrt{6}). In exams, identify (a,b) from (a+b) and \(2\sqrt{ab}\).
Step 2
Why this answer is correct
The correct answer is A. \((\sqrt{3}-\sqrt{2})^{2}\). (\(\sqrt{3}-\sqrt{2}\)^{2}=3+2-2\sqrt{6}=5-2\sqrt{6}). In exams, identify (a,b) from (a+b) and \(2\sqrt{ab}\).
Step 3
Exam Tip
(\(\sqrt{3}-\sqrt{2}\)^{2}=3+2-2\sqrt{6}=5-2\sqrt{6})। परीक्षा में (a+b) और \(2\sqrt{ab}\) से (a,b) पहचानें।
(\left\(\frac{2}{3}\right\)^{-3}=\left\(\frac{3}{2}\right\)^{3}=\frac{27}{8}) and (\left\(\frac{9}{4}\right\)^{-1}=\frac{4}{9}), so the product is (6). In exams, invert the fraction for negative powers.
Step 2
Why this answer is correct
The correct answer is A. (6). (\left\(\frac{2}{3}\right\)^{-3}=\left\(\frac{3}{2}\right\)^{3}=\frac{27}{8}) and (\left\(\frac{9}{4}\right\)^{-1}=\frac{4}{9}), so the product is (6). In exams, invert the fraction for negative powers.
Step 3
Exam Tip
(\left\(\frac{2}{3}\right\)^{-3}=\left\(\frac{3}{2}\right\)^{3}=\frac{27}{8}) और (\left\(\frac{9}{4}\right\)^{-1}=\frac{4}{9}), इसलिए गुणनफल (6) है। परीक्षा में ऋणात्मक घात पर भिन्न उलटें।
Here (x^{6}=\(x^{2}\)^{3}=27) and (x^{4}=\(x^{2}\)^{2}=9), so the difference is (18). In exams, express powers using the given \(x^{2}\).
Step 2
Why this answer is correct
The correct answer is A. (18). Here (x^{6}=\(x^{2}\)^{3}=27) and (x^{4}=\(x^{2}\)^{2}=9), so the difference is (18). In exams, express powers using the given \(x^{2}\).
Step 3
Exam Tip
(x^{6}=\(x^{2}\)^{3}=27) और (x^{4}=\(x^{2}\)^{2}=9), इसलिए अंतर (18) है। परीक्षा में दी हुई घात \(x^{2}\) के रूप में लिखें।
(\(a^{2}b^{-1}\)^{-3}=a^{-6}b^{3}), then \(\frac{a^{-6}b^{3}}{a^{-4}b^{2}}=a^{-2}b\). In exams, subtract powers of the same base during division.
Step 2
Why this answer is correct
The correct answer is A. \(a^{-2}b\). (\(a^{2}b^{-1}\)^{-3}=a^{-6}b^{3}), then \(\frac{a^{-6}b^{3}}{a^{-4}b^{2}}=a^{-2}b\). In exams, subtract powers of the same base during division.
Step 3
Exam Tip
(\(a^{2}b^{-1}\)^{-3}=a^{-6}b^{3}), फिर \(\frac{a^{-6}b^{3}}{a^{-4}b^{2}}=a^{-2}b\)। परीक्षा में भाग करते समय समान आधार की घात घटाएं।
(\left\(81x^{4}\right\)^{\frac{1}{2}}=\sqrt{81x^{4}}=9x^{2}). In exams, the exponent becomes half under a square root.
Step 2
Why this answer is correct
The correct answer is A. \(9x^{2}\). (\left\(81x^{4}\right\)^{\frac{1}{2}}=\sqrt{81x^{4}}=9x^{2}). In exams, the exponent becomes half under a square root.
Step 3
Exam Tip
(\left\(81x^{4}\right\)^{\frac{1}{2}}=\sqrt{81x^{4}}=9x^{2})। परीक्षा में वर्गमूल में घात आधी हो जाती है।
The total exponent on the left is (x+x+2-3=2x-1), and \(32=2^{5}\), so (2x-1=5), giving (x=3). In exams, convert the whole expression into one power.
Step 2
Why this answer is correct
The correct answer is B. (3). The total exponent on the left is (x+x+2-3=2x-1), and \(32=2^{5}\), so (2x-1=5), giving (x=3). In exams, convert the whole expression into one power.
Step 3
Exam Tip
बाएँ पक्ष की कुल घात (x+x+2-3=2x-1) है, और \(32=2^{5}\), इसलिए (2x-1=5) से (x=3)। परीक्षा में पूरी अभिव्यक्ति को एक ही घात में बदलें।
The first term becomes \(\sqrt{3}-\sqrt{2}\), and the second becomes \(\sqrt{3}+\sqrt{2}\), so the sum is \(2\sqrt{3}\). In exams, rationalize both denominators separately.
Step 2
Why this answer is correct
The correct answer is A. \(2\sqrt{3}\). The first term becomes \(\sqrt{3}-\sqrt{2}\), and the second becomes \(\sqrt{3}+\sqrt{2}\), so the sum is \(2\sqrt{3}\). In exams, rationalize both denominators separately.
Step 3
Exam Tip
पहला पद \(\sqrt{3}-\sqrt{2}\) और दूसरा पद \(\sqrt{3}+\sqrt{2}\) बनता है, इसलिए योग \(2\sqrt{3}\) है। परीक्षा में दोनों हरों को अलग-अलग परिमेय बनाएं।