SOLUTION: solve for X. log(X)-3log(X)=-2log2

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Question 969072: solve for X.
log(X)-3log(X)=-2log2
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
log%28x%29-3log%28x%29=-2log%282%29
log%28x%29-log%28x%5E3%29=log%282%5E%28-2%29%29
log%28%28x%2Fx%5E3%29%29=log%28%281%2F2%5E2%29%29
log%28%28cross%28x%291%2Fx%5Ecross%283%29%5E2%29%29=log%28%281%2F4%29%29
log%28%281%2Fx%5E2%29%29=log%28%281%2F4%29%29...if log same, then
1%2Fx%5E2=%281%2F4%29....cross multiply
1%2A4=1%2Ax%5E2
x%5E2=4
x=2 or x=-2=> disregard negative solution because log of negative number is undefined
so, your answer is: x=2