Question
Simplify the expression
xx2−1−2x
Evaluate
x−x1−2
Reduce fractions to a common denominator
xx×x−x1−x2x
Write all numerators above the common denominator
xx×x−1−2x
Solution
xx2−1−2x
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Find the excluded values
x=0
Evaluate
x−x1−2
Solution
x=0
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Find the roots
x1=1−2,x2=1+2
Alternative Form
x1≈−0.414214,x2≈2.414214
Evaluate
x−x1−2
To find the roots of the expression,set the expression equal to 0
x−x1−2=0
Find the domain
x−x1−2=0,x=0
Calculate
x−x1−2=0
Subtract the terms
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Simplify
x−x1
Reduce fractions to a common denominator
xx×x−x1
Write all numerators above the common denominator
xx×x−1
Multiply the terms
xx2−1
xx2−1−2=0
Subtract the terms
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Simplify
xx2−1−2
Reduce fractions to a common denominator
xx2−1−x2x
Write all numerators above the common denominator
xx2−1−2x
xx2−1−2x=0
Cross multiply
x2−1−2x=x×0
Simplify the equation
x2−1−2x=0
Rewrite in standard form
x2−2x−1=0
Substitute a=1,b=−2 and c=−1 into the quadratic formula x=2a−b±b2−4ac
x=22±(−2)2−4(−1)
Simplify the expression
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Evaluate
(−2)2−4(−1)
Simplify
(−2)2−(−4)
Rewrite the expression
22−(−4)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
22+4
Evaluate the power
4+4
Add the numbers
8
x=22±8
Simplify the radical expression
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Evaluate
8
Write the expression as a product where the root of one of the factors can be evaluated
4×2
Write the number in exponential form with the base of 2
22×2
The root of a product is equal to the product of the roots of each factor
22×2
Reduce the index of the radical and exponent with 2
22
x=22±22
Separate the equation into 2 possible cases
x=22+22x=22−22
Simplify the expression
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Evaluate
x=22+22
Divide the terms
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Evaluate
22+22
Rewrite the expression
22(1+2)
Reduce the fraction
1+2
x=1+2
x=1+2x=22−22
Simplify the expression
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Evaluate
x=22−22
Divide the terms
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Evaluate
22−22
Rewrite the expression
22(1−2)
Reduce the fraction
1−2
x=1−2
x=1+2x=1−2
Check if the solution is in the defined range
x=1+2x=1−2,x=0
Find the intersection of the solution and the defined range
x=1+2x=1−2
Solution
x1=1−2,x2=1+2
Alternative Form
x1≈−0.414214,x2≈2.414214
Show Solution
