Question

Determine o conjunto verdade das seguintes equações exponenciais

Answer 1

$a)\\\\ 4^x=16\\ 4^x=4^2\\ x=2\\\\ b)\\\\ 49^{2x+3}=343\\ (7^2)^{2x+3}=7^3\\ 7^{4x+6}=7^3\\ 4x+6=3\\ 4x=3-6\\ 4x=-3\\ x=\frac{-3}{4}\\\\ c)\\\\ 125^{x-9}=1\\ 125^{x-9}=125^0\\ x-9=0\\ x=9\\\\ d)\\\\ 2^{x+7}=\frac{1}{64}\\\\ 2^{x+7}=2^{-6}\\ x+7=-6\\ x=-6-7\\ x=-13$