Question

resultado da equação usando logaritmo 4^3x-1=72,5

Answer 1

$4^{3x-1}=72,5\\aplicar~log~dos~dois~lados:\\\displaystyle \ln4^{3x-1}=\ln72,5\implies (3x-1)=\frac{\ln72,5}{\ln4}\implies 3x-1=\log_472,5\\\log_472,5=\frac{\ln72,5}{\ln4}\approx\frac{4,28}{1,38}\approx3,1\\3x-1\approx3,1\implies 3x\approx3,1+1\implies x=\frac{4,1}{3}\approx\boxed{1,36}\\4^{3x-1}=72,5\implies 4^{3\cdot1,36-1}\implies 4^{3,08}\approx71,5$