Quantitative Aptitude Ques 412
Question: Simplify for the value of x. $ {{[{{[\sqrt[7]{({x^{-4/7}})}]}^{7/3}}]}^{21}}=\frac{1}{16} $
Options:
A) 1
B) 2
C) 3
D) 4
Show Answer
Answer:
Correct Answer: B
Solution:
- $ {{{{{[\sqrt[7]{{x^{-4/7}}}]}^{7/3}}}}^{21}}=\frac{1}{16} $
$ \Rightarrow $ $ {{{{{[{{({x^{-4/7}})}^{1/7}}]}^{7/3}}}}^{21}}=\frac{1}{16} $
$ \Rightarrow $ $ {{[{x^{-4/7}}]}^{1/3\times ,}}^{21}=\frac{1}{16} $
$ \Rightarrow $ $ {x^{-4}}={16^{-1}}={2^{-4}} $
$ \Rightarrow $ $ x=2 $
BETA
