Precalculus Examples

Find the Domain ((x^2-bx+ax-ab)/(x^2+bx-ax-ab))÷((x^2+bx+ax+ab)/(x^2-bx-ax+ab))
Step 1
Set the denominator in equal to to find where the expression is undefined.
Step 2
Solve for .
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Step 2.1
Use the quadratic formula to find the solutions.
Step 2.2
Substitute the values , , and into the quadratic formula and solve for .
Step 2.3
Simplify.
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Step 2.3.1
Simplify the numerator.
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Step 2.3.1.1
Apply the distributive property.
Step 2.3.1.2
Multiply .
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Step 2.3.1.2.1
Multiply by .
Step 2.3.1.2.2
Multiply by .
Step 2.3.1.3
Rewrite as .
Step 2.3.1.4
Expand using the FOIL Method.
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Step 2.3.1.4.1
Apply the distributive property.
Step 2.3.1.4.2
Apply the distributive property.
Step 2.3.1.4.3
Apply the distributive property.
Step 2.3.1.5
Simplify and combine like terms.
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Step 2.3.1.5.1
Simplify each term.
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Step 2.3.1.5.1.1
Multiply by .
Step 2.3.1.5.1.2
Rewrite using the commutative property of multiplication.
Step 2.3.1.5.1.3
Rewrite using the commutative property of multiplication.
Step 2.3.1.5.1.4
Multiply by by adding the exponents.
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Step 2.3.1.5.1.4.1
Move .
Step 2.3.1.5.1.4.2
Multiply by .
Step 2.3.1.5.1.5
Multiply by .
Step 2.3.1.5.1.6
Multiply by .
Step 2.3.1.5.2
Subtract from .
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Step 2.3.1.5.2.1
Move .
Step 2.3.1.5.2.2
Subtract from .
Step 2.3.1.6
Multiply .
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Step 2.3.1.6.1
Multiply by .
Step 2.3.1.6.2
Multiply by .
Step 2.3.1.7
Add and .
Step 2.3.1.8
Factor using the perfect square rule.
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Step 2.3.1.8.1
Rearrange terms.
Step 2.3.1.8.2
Check that the middle term is two times the product of the numbers being squared in the first term and third term.
Step 2.3.1.8.3
Rewrite the polynomial.
Step 2.3.1.8.4
Factor using the perfect square trinomial rule , where and .
Step 2.3.1.9
Pull terms out from under the radical, assuming positive real numbers.
Step 2.3.2
Multiply by .
Step 2.4
Simplify the expression to solve for the portion of the .
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Step 2.4.1
Simplify the numerator.
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Step 2.4.1.1
Apply the distributive property.
Step 2.4.1.2
Multiply .
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Step 2.4.1.2.1
Multiply by .
Step 2.4.1.2.2
Multiply by .
Step 2.4.1.3
Rewrite as .
Step 2.4.1.4
Expand using the FOIL Method.
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Step 2.4.1.4.1
Apply the distributive property.
Step 2.4.1.4.2
Apply the distributive property.
Step 2.4.1.4.3
Apply the distributive property.
Step 2.4.1.5
Simplify and combine like terms.
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Step 2.4.1.5.1
Simplify each term.
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Step 2.4.1.5.1.1
Multiply by .
Step 2.4.1.5.1.2
Rewrite using the commutative property of multiplication.
Step 2.4.1.5.1.3
Rewrite using the commutative property of multiplication.
Step 2.4.1.5.1.4
Multiply by by adding the exponents.
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Step 2.4.1.5.1.4.1
Move .
Step 2.4.1.5.1.4.2
Multiply by .
Step 2.4.1.5.1.5
Multiply by .
Step 2.4.1.5.1.6
Multiply by .
Step 2.4.1.5.2
Subtract from .
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Step 2.4.1.5.2.1
Move .
Step 2.4.1.5.2.2
Subtract from .
Step 2.4.1.6
Multiply .
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Step 2.4.1.6.1
Multiply by .
Step 2.4.1.6.2
Multiply by .
Step 2.4.1.7
Add and .
Step 2.4.1.8
Factor using the perfect square rule.
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Step 2.4.1.8.1
Rearrange terms.
Step 2.4.1.8.2
Check that the middle term is two times the product of the numbers being squared in the first term and third term.
Step 2.4.1.8.3
Rewrite the polynomial.
Step 2.4.1.8.4
Factor using the perfect square trinomial rule , where and .
Step 2.4.1.9
Pull terms out from under the radical, assuming positive real numbers.
Step 2.4.2
Multiply by .
Step 2.4.3
Change the to .
Step 2.4.4
Simplify the numerator.
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Step 2.4.4.1
Add and .
Step 2.4.4.2
Add and .
Step 2.4.4.3
Add and .
Step 2.4.5
Cancel the common factor of .
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Step 2.4.5.1
Cancel the common factor.
Step 2.4.5.2
Divide by .
Step 2.5
Simplify the expression to solve for the portion of the .
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Step 2.5.1
Simplify the numerator.
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Step 2.5.1.1
Apply the distributive property.
Step 2.5.1.2
Multiply .
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Step 2.5.1.2.1
Multiply by .
Step 2.5.1.2.2
Multiply by .
Step 2.5.1.3
Rewrite as .
Step 2.5.1.4
Expand using the FOIL Method.
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Step 2.5.1.4.1
Apply the distributive property.
Step 2.5.1.4.2
Apply the distributive property.
Step 2.5.1.4.3
Apply the distributive property.
Step 2.5.1.5
Simplify and combine like terms.
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Step 2.5.1.5.1
Simplify each term.
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Step 2.5.1.5.1.1
Multiply by .
Step 2.5.1.5.1.2
Rewrite using the commutative property of multiplication.
Step 2.5.1.5.1.3
Rewrite using the commutative property of multiplication.
Step 2.5.1.5.1.4
Multiply by by adding the exponents.
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Step 2.5.1.5.1.4.1
Move .
Step 2.5.1.5.1.4.2
Multiply by .
Step 2.5.1.5.1.5
Multiply by .
Step 2.5.1.5.1.6
Multiply by .
Step 2.5.1.5.2
Subtract from .
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Step 2.5.1.5.2.1
Move .
Step 2.5.1.5.2.2
Subtract from .
Step 2.5.1.6
Multiply .
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Step 2.5.1.6.1
Multiply by .
Step 2.5.1.6.2
Multiply by .
Step 2.5.1.7
Add and .
Step 2.5.1.8
Factor using the perfect square rule.
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Step 2.5.1.8.1
Rearrange terms.
Step 2.5.1.8.2
Check that the middle term is two times the product of the numbers being squared in the first term and third term.
Step 2.5.1.8.3
Rewrite the polynomial.
Step 2.5.1.8.4
Factor using the perfect square trinomial rule , where and .
Step 2.5.1.9
Pull terms out from under the radical, assuming positive real numbers.
Step 2.5.2
Multiply by .
Step 2.5.3
Change the to .
Step 2.5.4
Simplify the numerator.
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Step 2.5.4.1
Apply the distributive property.
Step 2.5.4.2
Subtract from .
Step 2.5.4.3
Subtract from .
Step 2.5.4.4
Add and .
Step 2.5.5
Cancel the common factor of and .
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Step 2.5.5.1
Factor out of .
Step 2.5.5.2
Cancel the common factors.
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Step 2.5.5.2.1
Factor out of .
Step 2.5.5.2.2
Cancel the common factor.
Step 2.5.5.2.3
Rewrite the expression.
Step 2.5.5.2.4
Divide by .
Step 2.6
The final answer is the combination of both solutions.
Step 3
Set the denominator in equal to to find where the expression is undefined.
Step 4
Solve for .
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Step 4.1
Use the quadratic formula to find the solutions.
Step 4.2
Substitute the values , , and into the quadratic formula and solve for .
Step 4.3
Simplify.
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Step 4.3.1
Simplify the numerator.
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Step 4.3.1.1
Apply the distributive property.
Step 4.3.1.2
Multiply .
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Step 4.3.1.2.1
Multiply by .
Step 4.3.1.2.2
Multiply by .
Step 4.3.1.3
Multiply .
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Step 4.3.1.3.1
Multiply by .
Step 4.3.1.3.2
Multiply by .
Step 4.3.1.4
Rewrite as .
Step 4.3.1.5
Expand using the FOIL Method.
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Step 4.3.1.5.1
Apply the distributive property.
Step 4.3.1.5.2
Apply the distributive property.
Step 4.3.1.5.3
Apply the distributive property.
Step 4.3.1.6
Simplify and combine like terms.
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Step 4.3.1.6.1
Simplify each term.
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Step 4.3.1.6.1.1
Rewrite using the commutative property of multiplication.
Step 4.3.1.6.1.2
Multiply by by adding the exponents.
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Step 4.3.1.6.1.2.1
Move .
Step 4.3.1.6.1.2.2
Multiply by .
Step 4.3.1.6.1.3
Multiply by .
Step 4.3.1.6.1.4
Multiply by .
Step 4.3.1.6.1.5
Rewrite using the commutative property of multiplication.
Step 4.3.1.6.1.6
Multiply by .
Step 4.3.1.6.1.7
Multiply by .
Step 4.3.1.6.1.8
Rewrite using the commutative property of multiplication.
Step 4.3.1.6.1.9
Multiply by .
Step 4.3.1.6.1.10
Multiply by .
Step 4.3.1.6.1.11
Rewrite using the commutative property of multiplication.
Step 4.3.1.6.1.12
Multiply by by adding the exponents.
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Step 4.3.1.6.1.12.1
Move .
Step 4.3.1.6.1.12.2
Multiply by .
Step 4.3.1.6.1.13
Multiply by .
Step 4.3.1.6.1.14
Multiply by .
Step 4.3.1.6.2
Add and .
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Step 4.3.1.6.2.1
Reorder and .
Step 4.3.1.6.2.2
Add and .
Step 4.3.1.7
Multiply by .
Step 4.3.1.8
Subtract from .
Step 4.3.1.9
Factor using the perfect square rule.
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Step 4.3.1.9.1
Rearrange terms.
Step 4.3.1.9.2
Check that the middle term is two times the product of the numbers being squared in the first term and third term.
Step 4.3.1.9.3
Rewrite the polynomial.
Step 4.3.1.9.4
Factor using the perfect square trinomial rule , where and .
Step 4.3.1.10
Pull terms out from under the radical, assuming positive real numbers.
Step 4.3.2
Multiply by .
Step 4.4
Simplify the expression to solve for the portion of the .
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Step 4.4.1
Simplify the numerator.
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Step 4.4.1.1
Apply the distributive property.
Step 4.4.1.2
Multiply .
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Step 4.4.1.2.1
Multiply by .
Step 4.4.1.2.2
Multiply by .
Step 4.4.1.3
Multiply .
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Step 4.4.1.3.1
Multiply by .
Step 4.4.1.3.2
Multiply by .
Step 4.4.1.4
Rewrite as .
Step 4.4.1.5
Expand using the FOIL Method.
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Step 4.4.1.5.1
Apply the distributive property.
Step 4.4.1.5.2
Apply the distributive property.
Step 4.4.1.5.3
Apply the distributive property.
Step 4.4.1.6
Simplify and combine like terms.
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Step 4.4.1.6.1
Simplify each term.
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Step 4.4.1.6.1.1
Rewrite using the commutative property of multiplication.
Step 4.4.1.6.1.2
Multiply by by adding the exponents.
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Step 4.4.1.6.1.2.1
Move .
Step 4.4.1.6.1.2.2
Multiply by .
Step 4.4.1.6.1.3
Multiply by .
Step 4.4.1.6.1.4
Multiply by .
Step 4.4.1.6.1.5
Rewrite using the commutative property of multiplication.
Step 4.4.1.6.1.6
Multiply by .
Step 4.4.1.6.1.7
Multiply by .
Step 4.4.1.6.1.8
Rewrite using the commutative property of multiplication.
Step 4.4.1.6.1.9
Multiply by .
Step 4.4.1.6.1.10
Multiply by .
Step 4.4.1.6.1.11
Rewrite using the commutative property of multiplication.
Step 4.4.1.6.1.12
Multiply by by adding the exponents.
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Step 4.4.1.6.1.12.1
Move .
Step 4.4.1.6.1.12.2
Multiply by .
Step 4.4.1.6.1.13
Multiply by .
Step 4.4.1.6.1.14
Multiply by .
Step 4.4.1.6.2
Add and .
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Step 4.4.1.6.2.1
Reorder and .
Step 4.4.1.6.2.2
Add and .
Step 4.4.1.7
Multiply by .
Step 4.4.1.8
Subtract from .
Step 4.4.1.9
Factor using the perfect square rule.
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Step 4.4.1.9.1
Rearrange terms.
Step 4.4.1.9.2
Check that the middle term is two times the product of the numbers being squared in the first term and third term.
Step 4.4.1.9.3
Rewrite the polynomial.
Step 4.4.1.9.4
Factor using the perfect square trinomial rule , where and .
Step 4.4.1.10
Pull terms out from under the radical, assuming positive real numbers.
Step 4.4.2
Multiply by .
Step 4.4.3
Change the to .
Step 4.4.4
Simplify the numerator.
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Step 4.4.4.1
Add and .
Step 4.4.4.2
Subtract from .
Step 4.4.4.3
Add and .
Step 4.4.5
Cancel the common factor of .
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Step 4.4.5.1
Cancel the common factor.
Step 4.4.5.2
Divide by .
Step 4.5
Simplify the expression to solve for the portion of the .
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Step 4.5.1
Simplify the numerator.
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Step 4.5.1.1
Apply the distributive property.
Step 4.5.1.2
Multiply .
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Step 4.5.1.2.1
Multiply by .
Step 4.5.1.2.2
Multiply by .
Step 4.5.1.3
Multiply .
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Step 4.5.1.3.1
Multiply by .
Step 4.5.1.3.2
Multiply by .
Step 4.5.1.4
Rewrite as .
Step 4.5.1.5
Expand using the FOIL Method.
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Step 4.5.1.5.1
Apply the distributive property.
Step 4.5.1.5.2
Apply the distributive property.
Step 4.5.1.5.3
Apply the distributive property.
Step 4.5.1.6
Simplify and combine like terms.
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Step 4.5.1.6.1
Simplify each term.
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Step 4.5.1.6.1.1
Rewrite using the commutative property of multiplication.
Step 4.5.1.6.1.2
Multiply by by adding the exponents.
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Step 4.5.1.6.1.2.1
Move .
Step 4.5.1.6.1.2.2
Multiply by .
Step 4.5.1.6.1.3
Multiply by .
Step 4.5.1.6.1.4
Multiply by .
Step 4.5.1.6.1.5
Rewrite using the commutative property of multiplication.
Step 4.5.1.6.1.6
Multiply by .
Step 4.5.1.6.1.7
Multiply by .
Step 4.5.1.6.1.8
Rewrite using the commutative property of multiplication.
Step 4.5.1.6.1.9
Multiply by .
Step 4.5.1.6.1.10
Multiply by .
Step 4.5.1.6.1.11
Rewrite using the commutative property of multiplication.
Step 4.5.1.6.1.12
Multiply by by adding the exponents.
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Step 4.5.1.6.1.12.1
Move .
Step 4.5.1.6.1.12.2
Multiply by .
Step 4.5.1.6.1.13
Multiply by .
Step 4.5.1.6.1.14
Multiply by .
Step 4.5.1.6.2
Add and .
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Step 4.5.1.6.2.1
Reorder and .
Step 4.5.1.6.2.2
Add and .
Step 4.5.1.7
Multiply by .
Step 4.5.1.8
Subtract from .
Step 4.5.1.9
Factor using the perfect square rule.
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Step 4.5.1.9.1
Rearrange terms.
Step 4.5.1.9.2
Check that the middle term is two times the product of the numbers being squared in the first term and third term.
Step 4.5.1.9.3
Rewrite the polynomial.
Step 4.5.1.9.4
Factor using the perfect square trinomial rule , where and .
Step 4.5.1.10
Pull terms out from under the radical, assuming positive real numbers.
Step 4.5.2
Multiply by .
Step 4.5.3
Change the to .
Step 4.5.4
Simplify the numerator.
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Step 4.5.4.1
Apply the distributive property.
Step 4.5.4.2
Multiply .
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Step 4.5.4.2.1
Multiply by .
Step 4.5.4.2.2
Multiply by .
Step 4.5.4.3
Subtract from .
Step 4.5.4.4
Add and .
Step 4.5.4.5
Add and .
Step 4.5.5
Cancel the common factor of .
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Step 4.5.5.1
Cancel the common factor.
Step 4.5.5.2
Divide by .
Step 4.6
The final answer is the combination of both solutions.
Step 5
Set the denominator in equal to to find where the expression is undefined.
Step 6
Solve for .
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Step 6.1
Set the numerator equal to zero.
Step 6.2
Solve the equation for .
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Step 6.2.1
Use the quadratic formula to find the solutions.
Step 6.2.2
Substitute the values , , and into the quadratic formula and solve for .
Step 6.2.3
Simplify.
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Step 6.2.3.1
Simplify the numerator.
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Step 6.2.3.1.1
Apply the distributive property.
Step 6.2.3.1.2
Rewrite as .
Step 6.2.3.1.3
Expand using the FOIL Method.
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Step 6.2.3.1.3.1
Apply the distributive property.
Step 6.2.3.1.3.2
Apply the distributive property.
Step 6.2.3.1.3.3
Apply the distributive property.
Step 6.2.3.1.4
Simplify and combine like terms.
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Step 6.2.3.1.4.1
Simplify each term.
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Step 6.2.3.1.4.1.1
Multiply by .
Step 6.2.3.1.4.1.2
Multiply by .
Step 6.2.3.1.4.2
Add and .
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Step 6.2.3.1.4.2.1
Reorder and .
Step 6.2.3.1.4.2.2
Add and .
Step 6.2.3.1.5
Multiply by .
Step 6.2.3.1.6
Subtract from .
Step 6.2.3.1.7
Factor using the perfect square rule.
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Step 6.2.3.1.7.1
Rearrange terms.
Step 6.2.3.1.7.2
Check that the middle term is two times the product of the numbers being squared in the first term and third term.
Step 6.2.3.1.7.3
Rewrite the polynomial.
Step 6.2.3.1.7.4
Factor using the perfect square trinomial rule , where and .
Step 6.2.3.1.8
Pull terms out from under the radical, assuming positive real numbers.
Step 6.2.3.2
Multiply by .
Step 6.2.4
Simplify the expression to solve for the portion of the .
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Step 6.2.4.1
Simplify the numerator.
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Step 6.2.4.1.1
Apply the distributive property.
Step 6.2.4.1.2
Rewrite as .
Step 6.2.4.1.3
Expand using the FOIL Method.
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Step 6.2.4.1.3.1
Apply the distributive property.
Step 6.2.4.1.3.2
Apply the distributive property.
Step 6.2.4.1.3.3
Apply the distributive property.
Step 6.2.4.1.4
Simplify and combine like terms.
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Step 6.2.4.1.4.1
Simplify each term.
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Step 6.2.4.1.4.1.1
Multiply by .
Step 6.2.4.1.4.1.2
Multiply by .
Step 6.2.4.1.4.2
Add and .
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Step 6.2.4.1.4.2.1
Reorder and .
Step 6.2.4.1.4.2.2
Add and .
Step 6.2.4.1.5
Multiply by .
Step 6.2.4.1.6
Subtract from .
Step 6.2.4.1.7
Factor using the perfect square rule.
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Step 6.2.4.1.7.1
Rearrange terms.
Step 6.2.4.1.7.2
Check that the middle term is two times the product of the numbers being squared in the first term and third term.
Step 6.2.4.1.7.3
Rewrite the polynomial.
Step 6.2.4.1.7.4
Factor using the perfect square trinomial rule , where and .
Step 6.2.4.1.8
Pull terms out from under the radical, assuming positive real numbers.
Step 6.2.4.2
Multiply by .
Step 6.2.4.3
Change the to .
Step 6.2.4.4
Simplify the numerator.
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Step 6.2.4.4.1
Add and .
Step 6.2.4.4.2
Add and .
Step 6.2.4.4.3
Subtract from .
Step 6.2.4.5
Cancel the common factor of and .
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Step 6.2.4.5.1
Factor out of .
Step 6.2.4.5.2
Cancel the common factors.
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Step 6.2.4.5.2.1
Factor out of .
Step 6.2.4.5.2.2
Cancel the common factor.
Step 6.2.4.5.2.3
Rewrite the expression.
Step 6.2.4.5.2.4
Divide by .
Step 6.2.5
Simplify the expression to solve for the portion of the .
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Step 6.2.5.1
Simplify the numerator.
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Step 6.2.5.1.1
Apply the distributive property.
Step 6.2.5.1.2
Rewrite as .
Step 6.2.5.1.3
Expand using the FOIL Method.
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Step 6.2.5.1.3.1
Apply the distributive property.
Step 6.2.5.1.3.2
Apply the distributive property.
Step 6.2.5.1.3.3
Apply the distributive property.
Step 6.2.5.1.4
Simplify and combine like terms.
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Step 6.2.5.1.4.1
Simplify each term.
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Step 6.2.5.1.4.1.1
Multiply by .
Step 6.2.5.1.4.1.2
Multiply by .
Step 6.2.5.1.4.2
Add and .
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Step 6.2.5.1.4.2.1
Reorder and .
Step 6.2.5.1.4.2.2
Add and .
Step 6.2.5.1.5
Multiply by .
Step 6.2.5.1.6
Subtract from .
Step 6.2.5.1.7
Factor using the perfect square rule.
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Step 6.2.5.1.7.1
Rearrange terms.
Step 6.2.5.1.7.2
Check that the middle term is two times the product of the numbers being squared in the first term and third term.
Step 6.2.5.1.7.3
Rewrite the polynomial.
Step 6.2.5.1.7.4
Factor using the perfect square trinomial rule , where and .
Step 6.2.5.1.8
Pull terms out from under the radical, assuming positive real numbers.
Step 6.2.5.2
Multiply by .
Step 6.2.5.3
Change the to .
Step 6.2.5.4
Simplify the numerator.
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Step 6.2.5.4.1
Apply the distributive property.
Step 6.2.5.4.2
Multiply .
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Step 6.2.5.4.2.1
Multiply by .
Step 6.2.5.4.2.2
Multiply by .
Step 6.2.5.4.3
Subtract from .
Step 6.2.5.4.4
Add and .
Step 6.2.5.4.5
Add and .
Step 6.2.5.5
Cancel the common factor of and .
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Step 6.2.5.5.1
Factor out of .
Step 6.2.5.5.2
Cancel the common factors.
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Step 6.2.5.5.2.1
Factor out of .
Step 6.2.5.5.2.2
Cancel the common factor.
Step 6.2.5.5.2.3
Rewrite the expression.
Step 6.2.5.5.2.4
Divide by .
Step 6.2.6
The final answer is the combination of both solutions.
Step 7
The domain is all real numbers.
Interval Notation:
Set-Builder Notation: