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Undoing ln

Part of the Exponentials, Logs & Sequences section of Coddy's Algebra 2 journey. Lesson 26 of 46.

Now the log is what is in the way. To solve ln⁡(x)=2\ln\left(x\right) = 2, read it as a power: the power of e that gives x is 2. So x=e2x = {e}^{2}, about 7.39.

Raising e to both sides does the same thing by algebra. eln⁡(x){e}^{\ln\left(x\right)} is x, because a power of e and ln undo each other. For a log base 3 you would raise 3 instead.

The answer is always positive, as an input to ln must be. Even ln⁡(x)=−1\ln\left(x\right) = -1 has a solution: x=e−1x = {e}^{-1}, about 0.37. A negative log only means x is between 0 and 1.

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Challenge

Solve ln⁡(x)=4\ln\left(x\right) = 4. Write the exact answer as a line of its own, x = ..., as a power of e.

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ln⁡(x)=4\ln\left(x\right) = 4

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