Question

Resolva as seguintes equações :


a) 2^3x= 512


b) 7^5× -2 = 7^1 - ×

Answer 1

Resposta:

$a)\\ 2^{3x}=512\\ \\ 2^{3x}=2^9\\ \\ cancela~~a~~base\\ \\ 3x=9\\ \\ x={9\over3}\\ \\ x=3$

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$b)\\ 7^{5x-2}=7^{1-x}\\ \\ 5x-2=1-x\\ \\ 5x+x=1+2\\ \\ 6x=3\\ \\ x={3\over6}~~~simplificando\\ \\ x={1\over2}$