[tex] > resolucao \\ \\ \geqslant progressao \: geometrica \\ \\ q = \frac{a2}{a1} \\ q = \frac{16}{ - 8} \\ q = - 2 \\ \\ \\ an = a1 \times q {}^{n - 1} \\ an = - 8 \times - 2 {}^{7 - 1} \\ an = - 8 \times - 2 {}^{6} \\ an = - 8 \times 64 \\ an = - 512 \\ \\ \\ > < > < > < > < > < > < > < > > [/tex]