Question 133252
log2 48 = log2(2^(x+2) - 2^x) 

log2 48 = log2(2^2*2^x - 2^x)

log2 48 = log2(2^x(4-1))

log2 48 = log2(3*2^x)

log2 48 = log2 3 + log2 2^x

log2 48 = log2 3 + x

x = log2 48 - log2 3

x = log2 (48/3)

x = log2 16

x = 4
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Cheers,
Stan H.