Question

The value of ' $x$ ' satisfying the equation $(\sqrt{5}{)}^{{\log }_5{5}^{{\log }_5{5}^{{\log }_5(x)}}}=2$ is

• A. 1
• B. 2
• C. 4
• D. 8

Answer 1

Answer: (C)

Using $a^{{\log }_{a}N}=N$ repeatedly, we get
$(\sqrt{5}{)}^{{\log }_{5}x}=2$
$(x{)}^{1/2}=2\Rightarrow x=4$