Question

2exp(m+1) + 2exp(m-1) = 640 find

Answer 1

Answer:

${2}^{m + 1} + {2}^{m - 1} = 640$

${2}^{m}(2 + \frac{1}{2} ) = 640$

${2}^{m} = 640 \times \frac{2}{5} = 128 \times 2 = 256 = {2}^{8}$

$m = 8$