Question

resoluçao:
log2(x²+2x-7)-log2(x-1)=2

Answer 1

Olá Ocrazy 

log2(x² + 2x - 7) - log2(x - 1) = 2

log(x² + 2x - 7) - log(x - 1) = 2log(2) = log(4)

(x² + 2x - 7)/(x - 1) = 4 

x² + 2x - 7 = 4x - 4 

x² - 2x - 3 = 0 

delta
d² = 4 + 12 = 16
d = 4

x = (2 + 4)/2 = 3

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