Calculus Examples
-6y(y+4)(y-2)−6y(y+4)(y−2)
Step 1
Step 1.1
For each factor in the denominator, create a new fraction using the factor as the denominator, and an unknown value as the numerator. Since the factor in the denominator is linear, put a single variable in its place AA.
Ay+4Ay+4
Step 1.2
For each factor in the denominator, create a new fraction using the factor as the denominator, and an unknown value as the numerator. Since the factor in the denominator is linear, put a single variable in its place BB.
Ay+4+By-2Ay+4+By−2
Step 1.3
Multiply each fraction in the equation by the denominator of the original expression. In this case, the denominator is (y+4)(y-2)(y+4)(y−2).
-6y(y+4)(y-2)(y+4)(y-2)=(A)(y+4)(y-2)y+4+(B)(y+4)(y-2)y-2−6y(y+4)(y−2)(y+4)(y−2)=(A)(y+4)(y−2)y+4+(B)(y+4)(y−2)y−2
Step 1.4
Cancel the common factor of y+4y+4.
Step 1.4.1
Cancel the common factor.
-6y(y+4)(y-2)(y+4)(y-2)=(A)(y+4)(y-2)y+4+(B)(y+4)(y-2)y-2−6y(y+4)(y−2)(y+4)(y−2)=(A)(y+4)(y−2)y+4+(B)(y+4)(y−2)y−2
Step 1.4.2
Rewrite the expression.
-6y(y-2)y-2=(A)(y+4)(y-2)y+4+(B)(y+4)(y-2)y-2−6y(y−2)y−2=(A)(y+4)(y−2)y+4+(B)(y+4)(y−2)y−2
-6y(y-2)y-2=(A)(y+4)(y-2)y+4+(B)(y+4)(y-2)y-2−6y(y−2)y−2=(A)(y+4)(y−2)y+4+(B)(y+4)(y−2)y−2
Step 1.5
Cancel the common factor of y-2y−2.
Step 1.5.1
Cancel the common factor.
-6y(y-2)y-2=(A)(y+4)(y-2)y+4+(B)(y+4)(y-2)y-2−6y(y−2)y−2=(A)(y+4)(y−2)y+4+(B)(y+4)(y−2)y−2
Step 1.5.2
Divide 6y6y by 11.
-(6y)=(A)(y+4)(y-2)y+4+(B)(y+4)(y-2)y-2−(6y)=(A)(y+4)(y−2)y+4+(B)(y+4)(y−2)y−2
-(6y)=(A)(y+4)(y-2)y+4+(B)(y+4)(y-2)y-2−(6y)=(A)(y+4)(y−2)y+4+(B)(y+4)(y−2)y−2
Step 1.6
Multiply 66 by -1−1.
-6y=(A)(y+4)(y-2)y+4+(B)(y+4)(y-2)y-2−6y=(A)(y+4)(y−2)y+4+(B)(y+4)(y−2)y−2
Step 1.7
Simplify each term.
Step 1.7.1
Cancel the common factor of y+4y+4.
Step 1.7.1.1
Cancel the common factor.
-6y=A(y+4)(y-2)y+4+(B)(y+4)(y-2)y-2−6y=A(y+4)(y−2)y+4+(B)(y+4)(y−2)y−2
Step 1.7.1.2
Divide (A)(y-2)(A)(y−2) by 11.
-6y=(A)(y-2)+(B)(y+4)(y-2)y-2−6y=(A)(y−2)+(B)(y+4)(y−2)y−2
-6y=(A)(y-2)+(B)(y+4)(y-2)y-2−6y=(A)(y−2)+(B)(y+4)(y−2)y−2
Step 1.7.2
Apply the distributive property.
-6y=Ay+A⋅-2+(B)(y+4)(y-2)y-2−6y=Ay+A⋅−2+(B)(y+4)(y−2)y−2
Step 1.7.3
Move -2−2 to the left of AA.
-6y=Ay-2⋅A+(B)(y+4)(y-2)y-2−6y=Ay−2⋅A+(B)(y+4)(y−2)y−2
Step 1.7.4
Cancel the common factor of y-2y−2.
Step 1.7.4.1
Cancel the common factor.
-6y=Ay-2A+(B)(y+4)(y-2)y-2−6y=Ay−2A+(B)(y+4)(y−2)y−2
Step 1.7.4.2
Divide (B)(y+4)(B)(y+4) by 11.
-6y=Ay-2A+(B)(y+4)−6y=Ay−2A+(B)(y+4)
-6y=Ay-2A+(B)(y+4)−6y=Ay−2A+(B)(y+4)
Step 1.7.5
Apply the distributive property.
-6y=Ay-2A+By+B⋅4−6y=Ay−2A+By+B⋅4
Step 1.7.6
Move 44 to the left of BB.
-6y=Ay-2A+By+4B−6y=Ay−2A+By+4B
-6y=Ay-2A+By+4B−6y=Ay−2A+By+4B
Step 1.8
Move -2A−2A.
-6y=Ay+By-2A+4B−6y=Ay+By−2A+4B
-6y=Ay+By-2A+4B−6y=Ay+By−2A+4B
Step 2
Step 2.1
Create an equation for the partial fraction variables by equating the coefficients of yy from each side of the equation. For the equation to be equal, the equivalent coefficients on each side of the equation must be equal.
-6=A+B−6=A+B
Step 2.2
Create an equation for the partial fraction variables by equating the coefficients of the terms not containing yy. For the equation to be equal, the equivalent coefficients on each side of the equation must be equal.
0=-2A+4B0=−2A+4B
Step 2.3
Set up the system of equations to find the coefficients of the partial fractions.
-6=A+B−6=A+B
0=-2A+4B0=−2A+4B
-6=A+B−6=A+B
0=-2A+4B0=−2A+4B
Step 3
Step 3.1
Solve for AA in -6=A+B−6=A+B.
Step 3.1.1
Rewrite the equation as A+B=-6A+B=−6.
A+B=-6A+B=−6
0=-2A+4B0=−2A+4B
Step 3.1.2
Subtract BB from both sides of the equation.
A=-6-BA=−6−B
0=-2A+4B0=−2A+4B
A=-6-BA=−6−B
0=-2A+4B0=−2A+4B
Step 3.2
Replace all occurrences of AA with -6-B−6−B in each equation.
Step 3.2.1
Replace all occurrences of AA in 0=-2A+4B0=−2A+4B with -6-B−6−B.
0=-2(-6-B)+4B0=−2(−6−B)+4B
A=-6-BA=−6−B
Step 3.2.2
Simplify the right side.
Step 3.2.2.1
Simplify -2(-6-B)+4B−2(−6−B)+4B.
Step 3.2.2.1.1
Simplify each term.
Step 3.2.2.1.1.1
Apply the distributive property.
0=-2⋅-6-2(-B)+4B0=−2⋅−6−2(−B)+4B
A=-6-BA=−6−B
Step 3.2.2.1.1.2
Multiply -2−2 by -6−6.
0=12-2(-B)+4B0=12−2(−B)+4B
A=-6-BA=−6−B
Step 3.2.2.1.1.3
Multiply -1−1 by -2−2.
0=12+2B+4B0=12+2B+4B
A=-6-BA=−6−B
0=12+2B+4B0=12+2B+4B
A=-6-BA=−6−B
Step 3.2.2.1.2
Add 2B2B and 4B4B.
0=12+6B0=12+6B
A=-6-BA=−6−B
0=12+6B0=12+6B
A=-6-BA=−6−B
0=12+6B0=12+6B
A=-6-BA=−6−B
0=12+6B0=12+6B
A=-6-BA=−6−B
Step 3.3
Solve for BB in 0=12+6B0=12+6B.
Step 3.3.1
Rewrite the equation as 12+6B=012+6B=0.
12+6B=012+6B=0
A=-6-BA=−6−B
Step 3.3.2
Subtract 1212 from both sides of the equation.
6B=-126B=−12
A=-6-BA=−6−B
Step 3.3.3
Divide each term in 6B=-126B=−12 by 66 and simplify.
Step 3.3.3.1
Divide each term in 6B=-126B=−12 by 66.
6B6=-1266B6=−126
A=-6-BA=−6−B
Step 3.3.3.2
Simplify the left side.
Step 3.3.3.2.1
Cancel the common factor of 66.
Step 3.3.3.2.1.1
Cancel the common factor.
6B6=-1266B6=−126
A=-6-BA=−6−B
Step 3.3.3.2.1.2
Divide BB by 11.
B=-126B=−126
A=-6-BA=−6−B
B=-126B=−126
A=-6-BA=−6−B
B=-126B=−126
A=-6-BA=−6−B
Step 3.3.3.3
Simplify the right side.
Step 3.3.3.3.1
Divide -12−12 by 66.
B=-2B=−2
A=-6-BA=−6−B
B=-2B=−2
A=-6-BA=−6−B
B=-2B=−2
A=-6-BA=−6−B
B=-2B=−2
A=-6-BA=−6−B
Step 3.4
Replace all occurrences of BB with -2−2 in each equation.
Step 3.4.1
Replace all occurrences of BB in A=-6-BA=−6−B with -2−2.
A=-6-(-2)A=−6−(−2)
B=-2B=−2
Step 3.4.2
Simplify the right side.
Step 3.4.2.1
Simplify -6-(-2)−6−(−2).
Step 3.4.2.1.1
Multiply -1−1 by -2−2.
A=-6+2A=−6+2
B=-2B=−2
Step 3.4.2.1.2
Add -6−6 and 22.
A=-4A=−4
B=-2B=−2
A=-4A=−4
B=-2B=−2
A=-4A=−4
B=-2B=−2
A=-4A=−4
B=-2B=−2
Step 3.5
List all of the solutions.
A=-4,B=-2A=−4,B=−2
A=-4,B=-2A=−4,B=−2
Step 4
Replace each of the partial fraction coefficients in Ay+4+By-2Ay+4+By−2 with the values found for AA and BB.
-4y+4+-2y-2−4y+4+−2y−2