Solve the equation for x. 3ln(x)+2ln(4)=ln(128)

Mathematics

1 answer:

Natasha2012 [34]3 years ago

7 0

Hello from MrBillDoesMath!

Answer: x = 2

Discussion:

As 3*ln(x) = ln (x^3) and 2 ln(4) = ln (4^2) the equation becomes

ln(x^3) + ln(4^2) = log(128) =>

ln (x^3 * 16) = log(128) =>

x^3 ^ 16 = 128 =>

x^3 = 128\16 = 8

If x cubed = 8, the the cube root is 2.

Thank you,

MrB

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