Open Question: Log(small 2)(x+2) + log(small 2)(x-2) = 5 (What did they do to the 5 on the right side to make it 32)?
18:50 Publicado por Flechado16
You got it wrong
log2(a) + log2(b) = log2(ab) = c
ab = 2^c where log2(a) = log base of a
So
log2(x+2) + log2(x-2) = 5 = log2{(x+2)(x-2)}
(x+2)(x-2) = 2^5 = 32
x^2 - 4 = 32 --> x^2 = 36 --> x = +/-6
Note if x = -6 --> x^2 - 4 = (-6)^2 -4 = 36 -4 =32
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