Verified answer

4^x - 2^(x + 1) - 24 = 0

4^x - 2*2^x - 24 = 0

2^x = y  > 0

y^2 - 2y - 24 = 0

D = 4 + 96 = 100

y12 = (2 +- 10)/2 =  6    -4

y1 = -4 < 0 нет

y = 6

2^x = 6

log(2) 2^x = log(2) 6

x = log(2) 6 = log(2) 2*3 = 1 + log(2) 3

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4^x + 2^(x + 1) - 24 = 0

........

y12 = (-2 +- 10)/2 =  -6    4

y1 = -6 < 0 нет

y = 4

2^x = 2^2

x = 2

это + если

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