A) 48
B) 88
C) 40
D) 44
Correct Answer: C
Solution :
\[x+\frac{1}{2x}=2\]\[\Rightarrow \]\[2x+\frac{2}{2x}=4\]\[\Rightarrow \]\[2x+\frac{1}{x}=4\] On cubing \[8{{x}^{3}}+\frac{1}{{{x}^{3}}}+3\cdot 2x\cdot \frac{1}{x}\left( 2x+\frac{1}{x} \right)=64\] \[\Rightarrow \] \[8{{x}^{3}}+\frac{1}{{{x}^{3}}}+6\times 4=64\] \[\Rightarrow \]\[8{{x}^{3}}+\frac{1}{{{x}^{3}}}=64-24=40\]
You need to login to perform this action.
You will be redirected in
3 sec
