2^x+2 = 8^x
I don't really understand how to do it...
I don't really understand how to do it...
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take the log of both sides
log 2^x+2 = log 8^x
Bring exponents to the front
x+2 log 2 = x log 8
x+2 = x log 8 / log 2
x+2 / x = log 8 / log 2
Using calculator, log 8 / log 2 = 3
x+2 / x = 3
3x = x+2
2x = 2
x = 1
log 2^x+2 = log 8^x
Bring exponents to the front
x+2 log 2 = x log 8
x+2 = x log 8 / log 2
x+2 / x = log 8 / log 2
Using calculator, log 8 / log 2 = 3
x+2 / x = 3
3x = x+2
2x = 2
x = 1
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If the equation is 2^(x+2) = 8^x, then noting that 8 = 2^3 we get
2^(x+2) = (2^3)^x = 2^(3x). Now equate exponents to get
x + 2 = 3x ---> 2 = 2x ---> x = 1.
2^(x+2) = (2^3)^x = 2^(3x). Now equate exponents to get
x + 2 = 3x ---> 2 = 2x ---> x = 1.
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