Question

ovalor de X é log×7=-1

Answer 1

$\log_x7=-1\Leftrightarrow x^{-1}=7\\\\\\x^{-1}=7\\\\x^{-1}=7^1\\\\x=7^{\frac{1}{-1}}\\\\x=7^{-1}\\\\x=\dfrac{1}{7}\\\\\\\boxed{S=\left\{\dfrac{1}{7}\right\}}$