Calculus Examples
∫x3+xx3-1dx
Step 1
Step 1.1
Set up the polynomials to be divided. If there is not a term for every exponent, insert one with a value of 0.
x3 | + | 0x2 | + | 0x | - | 1 | x3 | + | 0x2 | + | x | + | 0 |
Step 1.2
Divide the highest order term in the dividend x3 by the highest order term in divisor x3.
1 | |||||||||||||||
x3 | + | 0x2 | + | 0x | - | 1 | x3 | + | 0x2 | + | x | + | 0 |
Step 1.3
Multiply the new quotient term by the divisor.
1 | |||||||||||||||
x3 | + | 0x2 | + | 0x | - | 1 | x3 | + | 0x2 | + | x | + | 0 | ||
+ | x3 | + | 0 | + | 0 | - | 1 |
Step 1.4
The expression needs to be subtracted from the dividend, so change all the signs in x3+0+0-1
1 | |||||||||||||||
x3 | + | 0x2 | + | 0x | - | 1 | x3 | + | 0x2 | + | x | + | 0 | ||
- | x3 | - | 0 | - | 0 | + | 1 |
Step 1.5
After changing the signs, add the last dividend from the multiplied polynomial to find the new dividend.
1 | |||||||||||||||
x3 | + | 0x2 | + | 0x | - | 1 | x3 | + | 0x2 | + | x | + | 0 | ||
- | x3 | - | 0 | - | 0 | + | 1 | ||||||||
+ | x | + | 1 |
Step 1.6
The final answer is the quotient plus the remainder over the divisor.
∫1+x+1x3-1dx
∫1+x+1x3-1dx
Step 2
Split the single integral into multiple integrals.
∫dx+∫x+1x3-1dx
Step 3
Apply the constant rule.
x+C+∫x+1x3-1dx
Step 4
Step 4.1
Decompose the fraction and multiply through by the common denominator.
Step 4.1.1
Factor the fraction.
Step 4.1.1.1
Rewrite 1 as 13.
x+1x3-13
Step 4.1.1.2
Since both terms are perfect cubes, factor using the difference of cubes formula, a3-b3=(a-b)(a2+ab+b2) where a=x and b=1.
x+1(x-1)(x2+x⋅1+12)
Step 4.1.1.3
Simplify.
Step 4.1.1.3.1
Multiply x by 1.
x+1(x-1)(x2+x+12)
Step 4.1.1.3.2
One to any power is one.
x+1(x-1)(x2+x+1)
x+1(x-1)(x2+x+1)
x+1(x-1)(x2+x+1)
Step 4.1.2
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 A.
Ax-1
Step 4.1.3
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 is 2nd order, 2 terms are required in the numerator. The number of terms required in the numerator is always equal to the order of the factor in the denominator.
Ax-1+Bx+Cx2+x+1
Step 4.1.4
Multiply each fraction in the equation by the denominator of the original expression. In this case, the denominator is (x-1)(x2+x+1).
(x+1)(x-1)(x2+x+1)(x-1)(x2+x+1)=(A)(x-1)(x2+x+1)x-1+(Bx+C)(x-1)(x2+x+1)x2+x+1
Step 4.1.5
Cancel the common factor of x-1.
Step 4.1.5.1
Cancel the common factor.
(x+1)(x-1)(x2+x+1)(x-1)(x2+x+1)=(A)(x-1)(x2+x+1)x-1+(Bx+C)(x-1)(x2+x+1)x2+x+1
Step 4.1.5.2
Rewrite the expression.
(x+1)(x2+x+1)x2+x+1=(A)(x-1)(x2+x+1)x-1+(Bx+C)(x-1)(x2+x+1)x2+x+1
(x+1)(x2+x+1)x2+x+1=(A)(x-1)(x2+x+1)x-1+(Bx+C)(x-1)(x2+x+1)x2+x+1
Step 4.1.6
Cancel the common factor of x2+x+1.
Step 4.1.6.1
Cancel the common factor.
(x+1)(x2+x+1)x2+x+1=(A)(x-1)(x2+x+1)x-1+(Bx+C)(x-1)(x2+x+1)x2+x+1
Step 4.1.6.2
Divide x+1 by 1.
x+1=(A)(x-1)(x2+x+1)x-1+(Bx+C)(x-1)(x2+x+1)x2+x+1
x+1=(A)(x-1)(x2+x+1)x-1+(Bx+C)(x-1)(x2+x+1)x2+x+1
Step 4.1.7
Simplify each term.
Step 4.1.7.1
Cancel the common factor of x-1.
Step 4.1.7.1.1
Cancel the common factor.
x+1=A(x-1)(x2+x+1)x-1+(Bx+C)(x-1)(x2+x+1)x2+x+1
Step 4.1.7.1.2
Divide (A)(x2+x+1) by 1.
x+1=(A)(x2+x+1)+(Bx+C)(x-1)(x2+x+1)x2+x+1
x+1=(A)(x2+x+1)+(Bx+C)(x-1)(x2+x+1)x2+x+1
Step 4.1.7.2
Apply the distributive property.
x+1=Ax2+Ax+A⋅1+(Bx+C)(x-1)(x2+x+1)x2+x+1
Step 4.1.7.3
Multiply A by 1.
x+1=Ax2+Ax+A+(Bx+C)(x-1)(x2+x+1)x2+x+1
Step 4.1.7.4
Cancel the common factor of x2+x+1.
Step 4.1.7.4.1
Cancel the common factor.
x+1=Ax2+Ax+A+(Bx+C)(x-1)(x2+x+1)x2+x+1
Step 4.1.7.4.2
Divide (Bx+C)(x-1) by 1.
x+1=Ax2+Ax+A+(Bx+C)(x-1)
x+1=Ax2+Ax+A+(Bx+C)(x-1)
Step 4.1.7.5
Expand (Bx+C)(x-1) using the FOIL Method.
Step 4.1.7.5.1
Apply the distributive property.
x+1=Ax2+Ax+A+Bx(x-1)+C(x-1)
Step 4.1.7.5.2
Apply the distributive property.
x+1=Ax2+Ax+A+Bx⋅x+Bx⋅-1+C(x-1)
Step 4.1.7.5.3
Apply the distributive property.
x+1=Ax2+Ax+A+Bx⋅x+Bx⋅-1+Cx+C⋅-1
x+1=Ax2+Ax+A+Bx⋅x+Bx⋅-1+Cx+C⋅-1
Step 4.1.7.6
Simplify each term.
Step 4.1.7.6.1
Multiply x by x by adding the exponents.
Step 4.1.7.6.1.1
Move x.
x+1=Ax2+Ax+A+B(x⋅x)+Bx⋅-1+Cx+C⋅-1
Step 4.1.7.6.1.2
Multiply x by x.
x+1=Ax2+Ax+A+Bx2+Bx⋅-1+Cx+C⋅-1
x+1=Ax2+Ax+A+Bx2+Bx⋅-1+Cx+C⋅-1
Step 4.1.7.6.2
Move -1 to the left of Bx.
x+1=Ax2+Ax+A+Bx2-1⋅(Bx)+Cx+C⋅-1
Step 4.1.7.6.3
Rewrite -1(Bx) as -(Bx).
x+1=Ax2+Ax+A+Bx2-(Bx)+Cx+C⋅-1
Step 4.1.7.6.4
Move -1 to the left of C.
x+1=Ax2+Ax+A+Bx2-Bx+Cx-1⋅C
Step 4.1.7.6.5
Rewrite -1C as -C.
x+1=Ax2+Ax+A+Bx2-Bx+Cx-C
x+1=Ax2+Ax+A+Bx2-Bx+Cx-C
x+1=Ax2+Ax+A+Bx2-Bx+Cx-C
Step 4.1.8
Simplify the expression.
Step 4.1.8.1
Reorder B and x2.
x+1=Ax2+Ax+A+Bx2-Bx+Cx-C
Step 4.1.8.2
Move B.
x+1=Ax2+Ax+A+Bx2-1xB+Cx-C
Step 4.1.8.3
Move A.
x+1=Ax2+Ax+Bx2-1xB+Cx+A-C
Step 4.1.8.4
Move Ax.
x+1=Ax2+Bx2+Ax-1xB+Cx+A-C
x+1=Ax2+Bx2+Ax-1xB+Cx+A-C
x+1=Ax2+Bx2+Ax-1xB+Cx+A-C
Step 4.2
Create equations for the partial fraction variables and use them to set up a system of equations.
Step 4.2.1
Create an equation for the partial fraction variables by equating the coefficients of x2 from each side of the equation. For the equation to be equal, the equivalent coefficients on each side of the equation must be equal.
0=A+B
Step 4.2.2
Create an equation for the partial fraction variables by equating the coefficients of x from each side of the equation. For the equation to be equal, the equivalent coefficients on each side of the equation must be equal.
1=A-1B+C
Step 4.2.3
Create an equation for the partial fraction variables by equating the coefficients of the terms not containing x. For the equation to be equal, the equivalent coefficients on each side of the equation must be equal.
1=A-1C
Step 4.2.4
Set up the system of equations to find the coefficients of the partial fractions.
0=A+B
1=A-1B+C
1=A-1C
0=A+B
1=A-1B+C
1=A-1C
Step 4.3
Solve the system of equations.
Step 4.3.1
Solve for A in 0=A+B.
Step 4.3.1.1
Rewrite the equation as A+B=0.
A+B=0
1=A-1B+C
1=A-1C
Step 4.3.1.2
Subtract B from both sides of the equation.
A=-B
1=A-1B+C
1=A-1C
A=-B
1=A-1B+C
1=A-1C
Step 4.3.2
Replace all occurrences of A with -B in each equation.
Step 4.3.2.1
Replace all occurrences of A in 1=A-1B+C with -B.
1=(-B)-1B+C
A=-B
1=A-1C
Step 4.3.2.2
Simplify the right side.
Step 4.3.2.2.1
Simplify (-B)-1B+C.
Step 4.3.2.2.1.1
Rewrite -1B as -B.
1=-B-B+C
A=-B
1=A-1C
Step 4.3.2.2.1.2
Subtract B from -B.
1=-2B+C
A=-B
1=A-1C
1=-2B+C
A=-B
1=A-1C
1=-2B+C
A=-B
1=A-1C
Step 4.3.2.3
Replace all occurrences of A in 1=A-1C with -B.
1=(-B)-1C
1=-2B+C
A=-B
Step 4.3.2.4
Simplify the right side.
Step 4.3.2.4.1
Rewrite -1C as -C.
1=-B-C
1=-2B+C
A=-B
1=-B-C
1=-2B+C
A=-B
1=-B-C
1=-2B+C
A=-B
Step 4.3.3
Solve for C in 1=-2B+C.
Step 4.3.3.1
Rewrite the equation as -2B+C=1.
-2B+C=1
1=-B-C
A=-B
Step 4.3.3.2
Add 2B to both sides of the equation.
C=1+2B
1=-B-C
A=-B
C=1+2B
1=-B-C
A=-B
Step 4.3.4
Replace all occurrences of C with 1+2B in each equation.
Step 4.3.4.1
Replace all occurrences of C in 1=-B-C with 1+2B.
1=-B-(1+2B)
C=1+2B
A=-B
Step 4.3.4.2
Simplify the right side.
Step 4.3.4.2.1
Simplify -B-(1+2B).
Step 4.3.4.2.1.1
Simplify each term.
Step 4.3.4.2.1.1.1
Apply the distributive property.
1=-B-1⋅1-(2B)
C=1+2B
A=-B
Step 4.3.4.2.1.1.2
Multiply -1 by 1.
1=-B-1-(2B)
C=1+2B
A=-B
Step 4.3.4.2.1.1.3
Multiply 2 by -1.
1=-B-1-2B
C=1+2B
A=-B
1=-B-1-2B
C=1+2B
A=-B
Step 4.3.4.2.1.2
Subtract 2B from -B.
1=-3B-1
C=1+2B
A=-B
1=-3B-1
C=1+2B
A=-B
1=-3B-1
C=1+2B
A=-B
1=-3B-1
C=1+2B
A=-B
Step 4.3.5
Solve for B in 1=-3B-1.
Step 4.3.5.1
Rewrite the equation as -3B-1=1.
-3B-1=1
C=1+2B
A=-B
Step 4.3.5.2
Move all terms not containing B to the right side of the equation.
Step 4.3.5.2.1
Add 1 to both sides of the equation.
-3B=1+1
C=1+2B
A=-B
Step 4.3.5.2.2
Add 1 and 1.
-3B=2
C=1+2B
A=-B
-3B=2
C=1+2B
A=-B
Step 4.3.5.3
Divide each term in -3B=2 by -3 and simplify.
Step 4.3.5.3.1
Divide each term in -3B=2 by -3.
-3B-3=2-3
C=1+2B
A=-B
Step 4.3.5.3.2
Simplify the left side.
Step 4.3.5.3.2.1
Cancel the common factor of -3.
Step 4.3.5.3.2.1.1
Cancel the common factor.
-3B-3=2-3
C=1+2B
A=-B
Step 4.3.5.3.2.1.2
Divide B by 1.
B=2-3
C=1+2B
A=-B
B=2-3
C=1+2B
A=-B
B=2-3
C=1+2B
A=-B
Step 4.3.5.3.3
Simplify the right side.
Step 4.3.5.3.3.1
Move the negative in front of the fraction.
B=-23
C=1+2B
A=-B
B=-23
C=1+2B
A=-B
B=-23
C=1+2B
A=-B
B=-23
C=1+2B
A=-B
Step 4.3.6
Replace all occurrences of B with -23 in each equation.
Step 4.3.6.1
Replace all occurrences of B in C=1+2B with -23.
C=1+2(-23)
B=-23
A=-B
Step 4.3.6.2
Simplify the right side.
Step 4.3.6.2.1
Simplify 1+2(-23).
Step 4.3.6.2.1.1
Simplify each term.
Step 4.3.6.2.1.1.1
Multiply 2(-23).
Step 4.3.6.2.1.1.1.1
Multiply -1 by 2.
C=1-2(23)
B=-23
A=-B
Step 4.3.6.2.1.1.1.2
Combine -2 and 23.
C=1+-2⋅23
B=-23
A=-B
Step 4.3.6.2.1.1.1.3
Multiply -2 by 2.
C=1+-43
B=-23
A=-B
C=1+-43
B=-23
A=-B
Step 4.3.6.2.1.1.2
Move the negative in front of the fraction.
C=1-43
B=-23
A=-B
C=1-43
B=-23
A=-B
Step 4.3.6.2.1.2
Simplify the expression.
Step 4.3.6.2.1.2.1
Write 1 as a fraction with a common denominator.
C=33-43
B=-23
A=-B
Step 4.3.6.2.1.2.2
Combine the numerators over the common denominator.
C=3-43
B=-23
A=-B
Step 4.3.6.2.1.2.3
Subtract 4 from 3.
C=-13
B=-23
A=-B
Step 4.3.6.2.1.2.4
Move the negative in front of the fraction.
C=-13
B=-23
A=-B
C=-13
B=-23
A=-B
C=-13
B=-23
A=-B
C=-13
B=-23
A=-B
Step 4.3.6.3
Replace all occurrences of B in A=-B with -23.
A=-(-23)
C=-13
B=-23
Step 4.3.6.4
Simplify the right side.
Step 4.3.6.4.1
Multiply -(-23).
Step 4.3.6.4.1.1
Multiply -1 by -1.
A=1(23)
C=-13
B=-23
Step 4.3.6.4.1.2
Multiply 23 by 1.
A=23
C=-13
B=-23
A=23
C=-13
B=-23
A=23
C=-13
B=-23
A=23
C=-13
B=-23
Step 4.3.7
List all of the solutions.
A=23,C=-13,B=-23
A=23,C=-13,B=-23
Step 4.4
Replace each of the partial fraction coefficients in Ax-1+Bx+Cx2+x+1 with the values found for A, B, and C.
23x-1+-23x-13x2+x+1
Step 4.5
Simplify.
Step 4.5.1
Multiply the numerator and denominator of the fraction by 3.
Step 4.5.1.1
Multiply -23⋅x-13x2+x+1 by 33.
23x-1+33⋅-23x-13x2+x+1
Step 4.5.1.2
Combine.
23x-1+3(-23x-13)3(x2+x+1)
23x-1+3(-23x-13)3(x2+x+1)
Step 4.5.2
Apply the distributive property.
23x-1+3(-23x)+3(-13)3x2+3x+3⋅1
Step 4.5.3
Cancel the common factor of 3.
Step 4.5.3.1
Move the leading negative in -13 into the numerator.
23x-1+3(-23x)+3(-13)3x2+3x+3⋅1
Step 4.5.3.2
Cancel the common factor.
23x-1+3(-23x)+3(-13)3x2+3x+3⋅1
Step 4.5.3.3
Rewrite the expression.
23x-1+3(-23x)-13x2+3x+3⋅1
23x-1+3(-23x)-13x2+3x+3⋅1
Step 4.5.4
Simplify the numerator.
Step 4.5.4.1
Combine x and 23.
23x-1+3(-x⋅23)-13x2+3x+3⋅1
Step 4.5.4.2
Cancel the common factor of 3.
Step 4.5.4.2.1
Move the leading negative in -x⋅23 into the numerator.
23x-1+3(-x⋅23)-13x2+3x+3⋅1
Step 4.5.4.2.2
Cancel the common factor.
23x-1+3(-x⋅23)-13x2+3x+3⋅1
Step 4.5.4.2.3
Rewrite the expression.
23x-1+-x⋅2-13x2+3x+3⋅1
23x-1+-x⋅2-13x2+3x+3⋅1
Step 4.5.4.3
Multiply 2 by -1.
23x-1+-2x-13x2+3x+3⋅1
23x-1+-2x-13x2+3x+3⋅1
Step 4.5.5
Simplify with factoring out.
Step 4.5.5.1
Factor 3 out of 3x2+3x+3⋅1.
Step 4.5.5.1.1
Factor 3 out of 3x2.
23x-1+-2x-13(x2)+3x+3⋅1
Step 4.5.5.1.2
Factor 3 out of 3x.
23x-1+-2x-13(x2)+3(x)+3⋅1
Step 4.5.5.1.3
Factor 3 out of 3⋅1.
23x-1+-2x-13(x2)+3(x)+3(1)
Step 4.5.5.1.4
Factor 3 out of 3(x2)+3(x).
23x-1+-2x-13(x2+x)+3(1)
Step 4.5.5.1.5
Factor 3 out of 3(x2+x)+3(1).
23x-1+-2x-13(x2+x+1)
23x-1+-2x-13(x2+x+1)
Step 4.5.5.2
Factor -1 out of -2x.
23x-1+-(2x)-13(x2+x+1)
Step 4.5.5.3
Rewrite -1 as -1(1).
23x-1+-(2x)-1⋅13(x2+x+1)
Step 4.5.5.4
Factor -1 out of -(2x)-1(1).
23x-1+-(2x+1)3(x2+x+1)
Step 4.5.5.5
Simplify the expression.
Step 4.5.5.5.1
Rewrite -(2x+1) as -1(2x+1).
23x-1+-1(2x+1)3(x2+x+1)
Step 4.5.5.5.2
Move the negative in front of the fraction.
23x-1-2x+13(x2+x+1)
23x-1-2x+13(x2+x+1)
23x-1-2x+13(x2+x+1)
Step 4.5.6
Multiply the numerator by the reciprocal of the denominator.
23⋅1x-1-2x+13(x2+x+1)
Step 4.5.7
Multiply 23 by 1x-1.
x+C+∫23(x-1)-2x+13(x2+x+1)dx
x+C+∫23(x-1)-2x+13(x2+x+1)dx
x+C+∫23(x-1)-2x+13(x2+x+1)dx
Step 5
Split the single integral into multiple integrals.
x+C+∫23(x-1)dx+∫-2x+13(x2+x+1)dx
Step 6
Since 23 is constant with respect to x, move 23 out of the integral.
x+C+23∫1x-1dx+∫-2x+13(x2+x+1)dx
Step 7
Step 7.1
Let u1=x-1. Find du1dx.
Step 7.1.1
Differentiate x-1.
ddx[x-1]
Step 7.1.2
By the Sum Rule, the derivative of x-1 with respect to x is ddx[x]+ddx[-1].
ddx[x]+ddx[-1]
Step 7.1.3
Differentiate using the Power Rule which states that ddx[xn] is nxn-1 where n=1.
1+ddx[-1]
Step 7.1.4
Since -1 is constant with respect to x, the derivative of -1 with respect to x is 0.
1+0
Step 7.1.5
Add 1 and 0.
1
1
Step 7.2
Rewrite the problem using u1 and du1.
x+C+23∫1u1du1+∫-2x+13(x2+x+1)dx
x+C+23∫1u1du1+∫-2x+13(x2+x+1)dx
Step 8
The integral of 1u1 with respect to u1 is ln(|u1|).
x+C+23(ln(|u1|)+C)+∫-2x+13(x2+x+1)dx
Step 9
Since -1 is constant with respect to x, move -1 out of the integral.
x+C+23(ln(|u1|)+C)-∫2x+13(x2+x+1)dx
Step 10
Since 13 is constant with respect to x, move 13 out of the integral.
x+C+23(ln(|u1|)+C)-(13∫2x+1x2+x+1dx)
Step 11
Step 11.1
Let u2=x2+x+1. Find du2dx.
Step 11.1.1
Differentiate x2+x+1.
ddx[x2+x+1]
Step 11.1.2
By the Sum Rule, the derivative of x2+x+1 with respect to x is ddx[x2]+ddx[x]+ddx[1].
ddx[x2]+ddx[x]+ddx[1]
Step 11.1.3
Differentiate using the Power Rule which states that ddx[xn] is nxn-1 where n=2.
2x+ddx[x]+ddx[1]
Step 11.1.4
Differentiate using the Power Rule which states that ddx[xn] is nxn-1 where n=1.
2x+1+ddx[1]
Step 11.1.5
Since 1 is constant with respect to x, the derivative of 1 with respect to x is 0.
2x+1+0
Step 11.1.6
Add 2x+1 and 0.
2x+1
2x+1
Step 11.2
Rewrite the problem using u2 and du2.
x+C+23(ln(|u1|)+C)-13∫1u2du2
x+C+23(ln(|u1|)+C)-13∫1u2du2
Step 12
The integral of 1u2 with respect to u2 is ln(|u2|).
x+C+23(ln(|u1|)+C)-13(ln(|u2|)+C)
Step 13
Simplify.
x+23ln(|u1|)-13ln(|u2|)+C
Step 14
Step 14.1
Replace all occurrences of u1 with x-1.
x+23ln(|x-1|)-13ln(|u2|)+C
Step 14.2
Replace all occurrences of u2 with x2+x+1.
x+23ln(|x-1|)-13ln(|x2+x+1|)+C
x+23ln(|x-1|)-13ln(|x2+x+1|)+C