nilai (-9)pangkat -2 sama dengan a.81 b.-81 c.1/81 d.-1/81

[tex] { - 9}^{ - 2} = - ( \frac{1}{9} ) {}^{2} \\ = - \frac{1}{9} \times - \frac{1}{9} \\ = \frac{1}{81} [/tex]