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3 years ago

2^x-1=128 show work pls! thank u :)

Mathematics

1 answer:

hichkok12 [17]3 years ago

4 0

Hello from MrBillDoesMath!

Answer:

Take you pick below! (either x 8 or x = 7.01, approx, depending how the question is interpreted)

Discussion:

Interpretation 1

If the question is 2^(x -1) = 128, then as 2^7 = 128,

x-1 = 7 so x = 8

Interpretation 2

If the question is (2^x -1) = 128, then..

2^x = 128 + 1 = 129 =>

log(2^x) = log(129) =>

xlog(2) = log(129) =>

x = log (129) / log2 = 7.01

Regards,

MrB

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