Precalculus Examples

Solve for x ( log of (x)^2)=2 log of x
(log((x)2))=2log(x)
Step 1
Simplify 2log(x) by moving 2 inside the logarithm.
log((x)2)=log(x2)
Step 2
For the equation to be equal, the argument of the logarithms on both sides of the equation must be equal.
(x)2=x2
Step 3
Solve for x.
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Step 3.1
Since the exponents are equal, the bases of the exponents on both sides of the equation must be equal.
|x|=|x|
Step 3.2
Solve for x.
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Step 3.2.1
Rewrite the absolute value equation as four equations without absolute value bars.
x=x
x=-x
-x=x
-x=-x
Step 3.2.2
After simplifying, there are only two unique equations to be solved.
x=x
x=-x
Step 3.2.3
Solve x=x for x.
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Step 3.2.3.1
Move all terms containing x to the left side of the equation.
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Step 3.2.3.1.1
Subtract x from both sides of the equation.
x-x=0
Step 3.2.3.1.2
Subtract x from x.
0=0
0=0
Step 3.2.3.2
Since 0=0, the equation will always be true.
All real numbers
All real numbers
Step 3.2.4
Solve x=-x for x.
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Step 3.2.4.1
Move all terms containing x to the left side of the equation.
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Step 3.2.4.1.1
Add x to both sides of the equation.
x+x=0
Step 3.2.4.1.2
Add x and x.
2x=0
2x=0
Step 3.2.4.2
Divide each term in 2x=0 by 2 and simplify.
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Step 3.2.4.2.1
Divide each term in 2x=0 by 2.
2x2=02
Step 3.2.4.2.2
Simplify the left side.
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Step 3.2.4.2.2.1
Cancel the common factor of 2.
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Step 3.2.4.2.2.1.1
Cancel the common factor.
2x2=02
Step 3.2.4.2.2.1.2
Divide x by 1.
x=02
x=02
x=02
Step 3.2.4.2.3
Simplify the right side.
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Step 3.2.4.2.3.1
Divide 0 by 2.
x=0
x=0
x=0
x=0
Step 3.2.5
List all of the solutions.
x=0
x=0
x=0
Step 4
Exclude the solutions that do not make log((x)2)=2log(x) true.
No solution
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