SOLUTION: Solve: log2x = -1

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Question 267930: Solve:
log2x = -1
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
Is the equation
log%282%2C+%28x%29%29+=+-1
or
log%28%282x%29%29+=+-1

I will solve both. But if the correct equation is the first one, then you should indicate somehow that the base of the logarithm is 2. (You might want to "View the source" of this solution to see how I typed it to make it look like it does above.)

With both equations we start by rewriting the equation in exponential form.
log%282%2C+%28x%29%29+=+-1
x+=+2%5E%28-1%29
which simplifies to:
x+=+1%2F2

log%28%282x%29%29+=+-1
2x+=+10%5E%28-1%29
which simplifies to
2x+=+1%2F10
Dividing both sides by 2 we get:
x+=+1%2F20