SOLUTION: Find all real solutions x to 4^x - 2^x = 56.

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Question 1091459: Find all real solutions x to 4^x - 2^x = 56.
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
4^x - 2^x = 56
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2^(2x) - 2^x - 56 = 0
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(2^x + 7)*(2^x - 8) = 0
2^x = -7 NG
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2^x = 8
x = 3