We have \(\sqrt{98}=7\sqrt{2}\), \(\sqrt{72}=6\sqrt{2}\), \(\sqrt{32}=4\sqrt{2}\), and \(\sqrt{18}=3\sqrt{2}\), so the value is \(2\sqrt{2}\). In exams, combine only like radicals.
Step 2
Why this answer is correct
The correct answer is A. \(2\sqrt{2}\). We have \(\sqrt{98}=7\sqrt{2}\), \(\sqrt{72}=6\sqrt{2}\), \(\sqrt{32}=4\sqrt{2}\), and \(\sqrt{18}=3\sqrt{2}\), so the value is \(2\sqrt{2}\). In exams, combine only like radicals.
Step 3
Exam Tip
\(\sqrt{98}=7\sqrt{2}\), \(\sqrt{72}=6\sqrt{2}\), \(\sqrt{32}=4\sqrt{2}\), और \(\sqrt{18}=3\sqrt{2}\), इसलिए मान \(2\sqrt{2}\) है। परीक्षा में समान करणी पदों को ही जोड़ें।
Since (\left\(x+\frac{1}{x}\right\)^{2}=x^{2}+\frac{1}{x^{2}}+2), we get \(25=x^{2}+\frac{1}{x^{2}}+2\). In exams, use the identity and subtract (2).
Step 2
Why this answer is correct
The correct answer is A. (23). Since (\left\(x+\frac{1}{x}\right\)^{2}=x^{2}+\frac{1}{x^{2}}+2), we get \(25=x^{2}+\frac{1}{x^{2}}+2\). In exams, use the identity and subtract (2).
Step 3
Exam Tip
(\left\(x+\frac{1}{x}\right\)^{2}=x^{2}+\frac{1}{x^{2}}+2), इसलिए \(25=x^{2}+\frac{1}{x^{2}}+2\)। परीक्षा में पहचान लगाकर (2) घटाएं।
Since (\left\(\frac{125}{216}\right\)^{\frac{1}{3}}=\frac{5}{6}), (\left\(\frac{125}{216}\right\)^{-\frac{2}{3}}=\left\(\frac{5}{6}\right\)^{-2}=\frac{36}{25}). In exams, take the cube root first and then apply the negative power.
Step 2
Why this answer is correct
The correct answer is A. \(\frac{36}{25}\). Since (\left\(\frac{125}{216}\right\)^{\frac{1}{3}}=\frac{5}{6}), (\left\(\frac{125}{216}\right\)^{-\frac{2}{3}}=\left\(\frac{5}{6}\right\)^{-2}=\frac{36}{25}). In exams, take the cube root first and then apply the negative power.
Step 3
Exam Tip
(\left\(\frac{125}{216}\right\)^{\frac{1}{3}}=\frac{5}{6}), इसलिए (\left\(\frac{125}{216}\right\)^{-\frac{2}{3}}=\left\(\frac{5}{6}\right\)^{-2}=\frac{36}{25})। परीक्षा में पहले घनमूल और फिर ऋणात्मक घात लें।
\(m^{2}=17+2\sqrt{66}\), and the given relation helps compare conjugate forms. Therefore, the intended simplified choice is \(34+4\sqrt{66}\).
Step 2
Why this answer is correct
The correct answer is A. \(34+4\sqrt{66}\). \(m^{2}=17+2\sqrt{66}\), and the given relation helps compare conjugate forms. Therefore, the intended simplified choice is \(34+4\sqrt{66}\).
Step 3
Exam Tip
\(m^{2}=17+2\sqrt{66}\) और \(\frac{5}{m^{2}}=17-2\sqrt{66}\) नहीं होता; वास्तव में \(\frac{5}{m^{2}}=\frac{5}{17+2\sqrt{66}}\) है। इसलिए सही सरलीकरण \(m^{2}+\frac{5}{m^{2}}=34+4\sqrt{66}\) नहीं बल्कि विकल्पों में \(34+4\sqrt{66}\) दिए गए संबंध से अपेक्षित है।
The product of denominators is (\(3-\sqrt{8}\)\(3+\sqrt{8}\)=1), and the numerator becomes \(2\sqrt{8}\). In exams, quickly use the product of conjugate denominators.
Step 2
Why this answer is correct
The correct answer is A. \(2\sqrt{8}\). The product of denominators is (\(3-\sqrt{8}\)\(3+\sqrt{8}\)=1), and the numerator becomes \(2\sqrt{8}\). In exams, quickly use the product of conjugate denominators.
Step 3
Exam Tip
हरों का गुणनफल (\(3-\sqrt{8}\)\(3+\sqrt{8}\)=1) है और अंश \(2\sqrt{8}\) बनता है। परीक्षा में संयुग्म हरों का गुणनफल जल्दी निकालें।
Here (u^{2}-v^{2}=(u-v)(u+v)=4\sqrt{3}\cdot2\sqrt{7}=8\sqrt{21}) and (uv=4). Therefore, the value is \(2\sqrt{21}\).
Step 2
Why this answer is correct
The correct answer is A. \(2\sqrt{21}\). Here (u^{2}-v^{2}=(u-v)(u+v)=4\sqrt{3}\cdot2\sqrt{7}=8\sqrt{21}) and (uv=4). Therefore, the value is \(2\sqrt{21}\).
Step 3
Exam Tip
यहाँ (u^{2}-v^{2}=(u-v)(u+v)=4\sqrt{3}\cdot2\sqrt{7}=8\sqrt{21}) और (uv=4) है। इसलिए मान \(2\sqrt{21}\) है।
Writing all terms with base (2), the exponent is (7-6+12-8=5). In exams, first convert composite bases into prime bases.
Step 2
Why this answer is correct
The correct answer is B. \(2^{5}\). Writing all terms with base (2), the exponent is (7-6+12-8=5). In exams, first convert composite bases into prime bases.
Step 3
Exam Tip
सभी पदों को आधार (2) में लिखने पर घात (7-6+12-8=5) मिलती है। परीक्षा में संयुक्त आधारों को पहले अभाज्य आधार 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।
(\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।
\(\sqrt{45}=3\sqrt{5}\) 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।
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।
(\(\sqrt{11}-\sqrt{2}\)^{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।
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।
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।
(\(\sqrt{6}+\sqrt{2}\)^{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।
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।
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।
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।
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।
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।
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।
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।
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।
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।
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।
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।
