Do i let
2^2x = y
so it would be:
y^2 = 3y - 1?
2^2x = y
so it would be:
y^2 = 3y - 1?
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2^(2x + 1) = 3*(2^x) - 1
2*2^(2x) - 3*(2^x) + 1= 0
2*2^(2x) - 2*(2^x) - (2^x) + 1 = 0
(2*2^(x) - 1)(2^x - 1) = 0
2^x = 1/2 --> x = -1
2^x = 1 --> x = 0
2*2^(2x) - 3*(2^x) + 1= 0
2*2^(2x) - 2*(2^x) - (2^x) + 1 = 0
(2*2^(x) - 1)(2^x - 1) = 0
2^x = 1/2 --> x = -1
2^x = 1 --> x = 0
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use log on both sides
basically, 2^(2x+1) = 0
so 4^x = 0
hence when taking log, you can not solve as log(0) is undefined.
for 3(2^x) - 1 = 0
therefore 3(2^x) -= 1
and so 2^x = 1/3
now take log of both side gives
x log(2) = log(1/3)
x = log(1/3)/log(2)
basically, 2^(2x+1) = 0
so 4^x = 0
hence when taking log, you can not solve as log(0) is undefined.
for 3(2^x) - 1 = 0
therefore 3(2^x) -= 1
and so 2^x = 1/3
now take log of both side gives
x log(2) = log(1/3)
x = log(1/3)/log(2)