How do I solve an exponential equation with different bases?

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To solve the exponential equation 2^(x^2) * 4^(2x) = 1/8, it is essential to express all terms with the same base, which simplifies to 2^(3x^2) = 1/8. This leads to the equation 3x^2 * log(2) = log(1/8), allowing for the calculation of x^2. The discussion reveals that the problem ultimately results in a quadratic equation, which can yield two real roots. Participants emphasize the importance of careful work to avoid mistakes, particularly with exponent rules. The final consensus is that the equation produces two real solutions, correcting earlier assumptions of imaginary roots.
babacanoosh
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Hello all, I can't believe I having a hard time with this problem but...I am :cry:1. 2^(x^2) X 4^(2x) = 1/8
2. make the bases the same?
3.
2^(x^2) X 2^((2x)^2) = 1/8
2^(3x^(2)) = 1/8
3x^(2)log2=log1/8
(log1/8)/(log2) = 3x^(2)
x^(2) = -1


I know I am doing it wrong. Any help would be greatly appreciated. Thanks,
Baba
 
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(2^{2x})^2=2^{4x}
 
The general rule for "exponentiated exponents" is

(a^b)^c = a^{(b \cdot c), for a positive base a .

For this problem, you will end up with a quadratic equation in x, with two solutions.
 
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great! thanks so much. Just a stupid mistake on my part, I knew that :rolleyes:
 
I believe you end up with two imaginary solutions; My guess is that you should just show your work until you run into negative square root.
 
epkid08 said:
I believe you end up with two imaginary solutions; My guess is that you should just show your work until you run into negative square root.

You actually get two real roots.
 
I found the same, you should get two real roots.
 
Oh, I see what I did wrong, I had 2^{x^2}(2^x + 2^x)=1/8, instead of 2^{x^2}*2^x*2^x=1/8
 
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