SOLUTION: Solve the equation for x. log2(x) + log2(x - 1) = 1 I am coming up with x = {2, 1} but the application is telling me to "Check the syntax of your response." Please help. Al

Algebra ->  Equations -> SOLUTION: Solve the equation for x. log2(x) + log2(x - 1) = 1 I am coming up with x = {2, 1} but the application is telling me to "Check the syntax of your response." Please help. Al      Log On


   

Question 324938: Solve the equation for x.
log2(x) + log2(x - 1) = 1
I am coming up with x = {2, 1} but the application is telling me to "Check the syntax of your response."
Please help.
Alberto
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
I'll assume you meant log base 2:
log%282%2Cx%29+%2B+log%282%2C%28x+-+1%29%29+=+1
log%282%2Cx%28x+-+1%29%29+=+1
x%28x+-+1%29+=+2%5E1
x%5E2+-+x+=+2
x%5E2+-+x+-+2+=+0
%28x-2%29%28x%2B1%29+=+0
x = {-1, 2}
.
But wait, -1 is an extraneous solution toss it out. Leaving you with:
x = 2