Question

Simplify: $\{{\left(\frac{1}{5}\right)}^{-2}-{\left(\frac{1}{6}\right)}^{-2}{\left(\frac{1}{3}\right)}^{-2}\}$

Answer 1

$\left\{\right(\frac{1}{5}{)}^{-2}-\left(\frac{1}{6}{)}^{-2}\right(\frac{1}{3}{)}^{-2}\}$

$\Rightarrow \left\{\right(5^{-1}{)}^{-2}-\left(6^{-1}{)}^{-2}\right(3^{-1}{)}^{-2}\}$

$\Rightarrow \{5^2-6^2{3}^2\}$

$\Rightarrow \{25-36\times 9\}$

$\Rightarrow 25-324=-299$