Question

Решите пример (0.3^(-2)-1.5^(-2))/(4.5^(-1)+1.5^(-1))

Answer 1

$(0.3^{-2}-1.5^{-2})/(4.5^{-1}+1.5^{-1})= \\ \\ ( \frac{1}{0.09} - \frac{1}{2.25} )/( \frac{1}{4.5} + \frac{1}{1.5} )= \\ \\ \frac{2.25-0.09}{0.09*2.25} / \frac{1+3}{4.5} = \\ \\ \frac{2.16}{0.2025} * \frac{4.5}{4} = \frac{9.72}{0.81} =12$