Calculus Examples
y=-7x2+21xy=−7x2+21x , y=3xy=3x
Step 1
To find the volume of the solid, first define the area of each slice then integrate across the range. The area of each slice is the area of a circle with radius f(x)f(x) and A=πr2A=πr2.
V=π∫2.‾5714280(f(x))2-(g(x))2dxV=π∫2.¯¯¯¯¯¯¯¯¯¯¯¯5714280(f(x))2−(g(x))2dx where f(x)=-7x2+21xf(x)=−7x2+21x and g(x)=3xg(x)=3x
Step 2
Step 2.1
Simplify each term.
Step 2.1.1
Rewrite (-7x2+21x)2(−7x2+21x)2 as (-7x2+21x)(-7x2+21x)(−7x2+21x)(−7x2+21x).
V=(-7x2+21x)(-7x2+21x)-(3x)2V=(−7x2+21x)(−7x2+21x)−(3x)2
Step 2.1.2
Expand (-7x2+21x)(-7x2+21x)(−7x2+21x)(−7x2+21x) using the FOIL Method.
Step 2.1.2.1
Apply the distributive property.
V=-7x2(-7x2+21x)+21x(-7x2+21x)-(3x)2V=−7x2(−7x2+21x)+21x(−7x2+21x)−(3x)2
Step 2.1.2.2
Apply the distributive property.
V=-7x2(-7x2)-7x2(21x)+21x(-7x2+21x)-(3x)2V=−7x2(−7x2)−7x2(21x)+21x(−7x2+21x)−(3x)2
Step 2.1.2.3
Apply the distributive property.
V=-7x2(-7x2)-7x2(21x)+21x(-7x2)+21x(21x)-(3x)2V=−7x2(−7x2)−7x2(21x)+21x(−7x2)+21x(21x)−(3x)2
V=-7x2(-7x2)-7x2(21x)+21x(-7x2)+21x(21x)-(3x)2V=−7x2(−7x2)−7x2(21x)+21x(−7x2)+21x(21x)−(3x)2
Step 2.1.3
Simplify and combine like terms.
Step 2.1.3.1
Simplify each term.
Step 2.1.3.1.1
Rewrite using the commutative property of multiplication.
V=-7⋅(-7x2x2)-7x2(21x)+21x(-7x2)+21x(21x)-(3x)2V=−7⋅(−7x2x2)−7x2(21x)+21x(−7x2)+21x(21x)−(3x)2
Step 2.1.3.1.2
Multiply x2x2 by x2x2 by adding the exponents.
Step 2.1.3.1.2.1
Move x2x2.
V=-7⋅(-7(x2x2))-7x2(21x)+21x(-7x2)+21x(21x)-(3x)2V=−7⋅(−7(x2x2))−7x2(21x)+21x(−7x2)+21x(21x)−(3x)2
Step 2.1.3.1.2.2
Use the power rule aman=am+n to combine exponents.
V=-7⋅(-7x2+2)-7x2(21x)+21x(-7x2)+21x(21x)-(3x)2
Step 2.1.3.1.2.3
Add 2 and 2.
V=-7⋅(-7x4)-7x2(21x)+21x(-7x2)+21x(21x)-(3x)2
V=-7⋅(-7x4)-7x2(21x)+21x(-7x2)+21x(21x)-(3x)2
Step 2.1.3.1.3
Multiply -7 by -7.
V=49x4-7x2(21x)+21x(-7x2)+21x(21x)-(3x)2
Step 2.1.3.1.4
Rewrite using the commutative property of multiplication.
V=49x4-7⋅(21x2x)+21x(-7x2)+21x(21x)-(3x)2
Step 2.1.3.1.5
Multiply x2 by x by adding the exponents.
Step 2.1.3.1.5.1
Move x.
V=49x4-7⋅(21(x⋅x2))+21x(-7x2)+21x(21x)-(3x)2
Step 2.1.3.1.5.2
Multiply x by x2.
Step 2.1.3.1.5.2.1
Raise x to the power of 1.
V=49x4-7⋅(21(x⋅x2))+21x(-7x2)+21x(21x)-(3x)2
Step 2.1.3.1.5.2.2
Use the power rule aman=am+n to combine exponents.
V=49x4-7⋅(21x1+2)+21x(-7x2)+21x(21x)-(3x)2
V=49x4-7⋅(21x1+2)+21x(-7x2)+21x(21x)-(3x)2
Step 2.1.3.1.5.3
Add 1 and 2.
V=49x4-7⋅(21x3)+21x(-7x2)+21x(21x)-(3x)2
V=49x4-7⋅(21x3)+21x(-7x2)+21x(21x)-(3x)2
Step 2.1.3.1.6
Multiply -7 by 21.
V=49x4-147x3+21x(-7x2)+21x(21x)-(3x)2
Step 2.1.3.1.7
Rewrite using the commutative property of multiplication.
V=49x4-147x3+21⋅(-7x⋅x2)+21x(21x)-(3x)2
Step 2.1.3.1.8
Multiply x by x2 by adding the exponents.
Step 2.1.3.1.8.1
Move x2.
V=49x4-147x3+21⋅(-7(x2x))+21x(21x)-(3x)2
Step 2.1.3.1.8.2
Multiply x2 by x.
Step 2.1.3.1.8.2.1
Raise x to the power of 1.
V=49x4-147x3+21⋅(-7(x2x))+21x(21x)-(3x)2
Step 2.1.3.1.8.2.2
Use the power rule aman=am+n to combine exponents.
V=49x4-147x3+21⋅(-7x2+1)+21x(21x)-(3x)2
V=49x4-147x3+21⋅(-7x2+1)+21x(21x)-(3x)2
Step 2.1.3.1.8.3
Add 2 and 1.
V=49x4-147x3+21⋅(-7x3)+21x(21x)-(3x)2
V=49x4-147x3+21⋅(-7x3)+21x(21x)-(3x)2
Step 2.1.3.1.9
Multiply 21 by -7.
V=49x4-147x3-147x3+21x(21x)-(3x)2
Step 2.1.3.1.10
Rewrite using the commutative property of multiplication.
V=49x4-147x3-147x3+21⋅(21x⋅x)-(3x)2
Step 2.1.3.1.11
Multiply x by x by adding the exponents.
Step 2.1.3.1.11.1
Move x.
V=49x4-147x3-147x3+21⋅(21(x⋅x))-(3x)2
Step 2.1.3.1.11.2
Multiply x by x.
V=49x4-147x3-147x3+21⋅(21x2)-(3x)2
V=49x4-147x3-147x3+21⋅(21x2)-(3x)2
Step 2.1.3.1.12
Multiply 21 by 21.
V=49x4-147x3-147x3+441x2-(3x)2
V=49x4-147x3-147x3+441x2-(3x)2
Step 2.1.3.2
Subtract 147x3 from -147x3.
V=49x4-294x3+441x2-(3x)2
V=49x4-294x3+441x2-(3x)2
Step 2.1.4
Apply the product rule to 3x.
V=49x4-294x3+441x2-(32x2)
Step 2.1.5
Raise 3 to the power of 2.
V=49x4-294x3+441x2-(9x2)
Step 2.1.6
Multiply 9 by -1.
V=49x4-294x3+441x2-9x2
V=49x4-294x3+441x2-9x2
Step 2.2
Subtract 9x2 from 441x2.
V=49x4-294x3+432x2
V=49x4-294x3+432x2
Step 3
Split the single integral into multiple integrals.
V=π(∫2.‾571428049x4dx+∫2.‾5714280-294x3dx+∫2.‾5714280432x2dx)
Step 4
Since 49 is constant with respect to x, move 49 out of the integral.
V=π(49∫2.‾5714280x4dx+∫2.‾5714280-294x3dx+∫2.‾5714280432x2dx)
Step 5
By the Power Rule, the integral of x4 with respect to x is 15x5.
V=π(49(15x5]2.‾5714280)+∫2.‾5714280-294x3dx+∫2.‾5714280432x2dx)
Step 6
Combine 15 and x5.
V=π(49(x55]2.‾5714280)+∫2.‾5714280-294x3dx+∫2.‾5714280432x2dx)
Step 7
Since -294 is constant with respect to x, move -294 out of the integral.
V=π(49(x55]2.‾5714280)-294∫2.‾5714280x3dx+∫2.‾5714280432x2dx)
Step 8
By the Power Rule, the integral of x3 with respect to x is 14x4.
V=π(49(x55]2.‾5714280)-294(14x4]2.‾5714280)+∫2.‾5714280432x2dx)
Step 9
Combine 14 and x4.
V=π(49(x55]2.‾5714280)-294(x44]2.‾5714280)+∫2.‾5714280432x2dx)
Step 10
Since 432 is constant with respect to x, move 432 out of the integral.
V=π(49(x55]2.‾5714280)-294(x44]2.‾5714280)+432∫2.‾5714280x2dx)
Step 11
By the Power Rule, the integral of x2 with respect to x is 13x3.
V=π(49(x55]2.‾5714280)-294(x44]2.‾5714280)+432(13x3]2.‾5714280))
Step 12
Step 12.1
Combine 13 and x3.
V=π(49(x55]2.‾5714280)-294(x44]2.‾5714280)+432(x33]2.‾5714280))
Step 12.2
Substitute and simplify.
Step 12.2.1
Evaluate x55 at 2.‾571428 and at 0.
V=π(49((2.‾57142855)-055)-294(x44]2.‾5714280)+432(x33]2.‾5714280))
Step 12.2.2
Evaluate x44 at 2.‾571428 and at 0.
V=π(49(2.‾57142855-055)-294(2.‾57142844-044)+432(x33]2.‾5714280))
Step 12.2.3
Evaluate x33 at 2.‾571428 and at 0.
V=π(49(2.‾57142855-055)-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4
Simplify.
Step 12.2.4.1
Raise 2.‾571428 to the power of 5.
V=π(49(112.427440945-055)-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4.2
Raising 0 to any positive power yields 0.
V=π(49(112.427440945-05)-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4.3
Cancel the common factor of 0 and 5.
Step 12.2.4.3.1
Factor 5 out of 0.
V=π(49(112.427440945-5(0)5)-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4.3.2
Cancel the common factors.
Step 12.2.4.3.2.1
Factor 5 out of 5.
V=π(49(112.427440945-5⋅05⋅1)-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4.3.2.2
Cancel the common factor.
V=π(49(112.427440945-5⋅05⋅1)-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4.3.2.3
Rewrite the expression.
V=π(49(112.427440945-01)-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4.3.2.4
Divide 0 by 1.
V=π(49(112.427440945-0)-294(2.‾57142844-044)+432((2.‾57142833)-033))
V=π(49(112.427440945-0)-294(2.‾57142844-044)+432((2.‾57142833)-033))
V=π(49(112.427440945-0)-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4.4
Multiply -1 by 0.
V=π(49(112.427440945+0)-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4.5
Add 112.427440945 and 0.
V=π(49(112.427440945)-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4.6
Combine 49 and 112.427440945.
V=π(49⋅112.427440945-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4.7
Multiply 49 by 112.42744094.
V=π(5508.944606415-294(2.‾57142844-044)+432((2.‾57142833)-033))
Step 12.2.4.8
Raise 2.‾571428 to the power of 4.
V=π(5508.944606415-294(43.721782594-044)+432((2.‾57142833)-033))
Step 12.2.4.9
Raising 0 to any positive power yields 0.
V=π(5508.944606415-294(43.721782594-04)+432((2.‾57142833)-033))
Step 12.2.4.10
Cancel the common factor of 0 and 4.
Step 12.2.4.10.1
Factor 4 out of 0.
V=π(5508.944606415-294(43.721782594-4(0)4)+432((2.‾57142833)-033))
Step 12.2.4.10.2
Cancel the common factors.
Step 12.2.4.10.2.1
Factor 4 out of 4.
V=π(5508.944606415-294(43.721782594-4⋅04⋅1)+432((2.‾57142833)-033))
Step 12.2.4.10.2.2
Cancel the common factor.
V=π(5508.944606415-294(43.721782594-4⋅04⋅1)+432((2.‾57142833)-033))
Step 12.2.4.10.2.3
Rewrite the expression.
V=π(5508.944606415-294(43.721782594-01)+432((2.‾57142833)-033))
Step 12.2.4.10.2.4
Divide 0 by 1.
V=π(5508.944606415-294(43.721782594-0)+432((2.‾57142833)-033))
V=π(5508.944606415-294(43.721782594-0)+432((2.‾57142833)-033))
V=π(5508.944606415-294(43.721782594-0)+432((2.‾57142833)-033))
Step 12.2.4.11
Multiply -1 by 0.
V=π(5508.944606415-294(43.721782594+0)+432((2.‾57142833)-033))
Step 12.2.4.12
Add 43.721782594 and 0.
V=π(5508.944606415-294(43.721782594)+432((2.‾57142833)-033))
Step 12.2.4.13
Combine -294 and 43.721782594.
V=π(5508.944606415+-294⋅43.721782594+432((2.‾57142833)-033))
Step 12.2.4.14
Multiply -294 by 43.72178259.
V=π(5508.944606415+-12854.204081634+432((2.‾57142833)-033))
Step 12.2.4.15
Move the negative in front of the fraction.
V=π(5508.944606415-12854.204081634+432((2.‾57142833)-033))
Step 12.2.4.16
To write 5508.944606415 as a fraction with a common denominator, multiply by 44.
V=π(5508.944606415⋅44-12854.204081634+432((2.‾57142833)-033))
Step 12.2.4.17
To write -12854.204081634 as a fraction with a common denominator, multiply by 55.
V=π(5508.944606415⋅44-12854.204081634⋅55+432((2.‾57142833)-033))
Step 12.2.4.18
Write each expression with a common denominator of 20, by multiplying each by an appropriate factor of 1.
Step 12.2.4.18.1
Multiply 5508.944606415 by 44.
V=π(5508.94460641⋅45⋅4-12854.204081634⋅55+432((2.‾57142833)-033))
Step 12.2.4.18.2
Multiply 5 by 4.
V=π(5508.94460641⋅420-12854.204081634⋅55+432((2.‾57142833)-033))
Step 12.2.4.18.3
Multiply 12854.204081634 by 55.
V=π(5508.94460641⋅420-12854.20408163⋅54⋅5+432((2.‾57142833)-033))
Step 12.2.4.18.4
Multiply 4 by 5.
V=π(5508.94460641⋅420-12854.20408163⋅520+432((2.‾57142833)-033))
V=π(5508.94460641⋅420-12854.20408163⋅520+432((2.‾57142833)-033))
Step 12.2.4.19
Combine the numerators over the common denominator.
V=π(5508.94460641⋅4-12854.20408163⋅520+432((2.‾57142833)-033))
Step 12.2.4.20
Multiply 5508.94460641 by 4.
V=π(22035.77842565-12854.20408163⋅520+432((2.‾57142833)-033))
Step 12.2.4.21
Multiply -12854.20408163 by 5.
V=π(22035.77842565-64271.0204081620+432((2.‾57142833)-033))
Step 12.2.4.22
Subtract 64271.02040816 from 22035.77842565.
V=π(-42235.241982520+432((2.‾57142833)-033))
Step 12.2.4.23
Move the negative in front of the fraction.
V=π(-42235.241982520+432((2.‾57142833)-033))
Step 12.2.4.24
Raise 2.‾571428 to the power of 3.
V=π(-42235.241982520+432(17.002915453-033))
Step 12.2.4.25
Raising 0 to any positive power yields 0.
V=π(-42235.241982520+432(17.002915453-03))
Step 12.2.4.26
Cancel the common factor of 0 and 3.
Step 12.2.4.26.1
Factor 3 out of 0.
V=π(-42235.241982520+432(17.002915453-3(0)3))
Step 12.2.4.26.2
Cancel the common factors.
Step 12.2.4.26.2.1
Factor 3 out of 3.
V=π(-42235.241982520+432(17.002915453-3⋅03⋅1))
Step 12.2.4.26.2.2
Cancel the common factor.
V=π(-42235.241982520+432(17.002915453-3⋅03⋅1))
Step 12.2.4.26.2.3
Rewrite the expression.
V=π(-42235.241982520+432(17.002915453-01))
Step 12.2.4.26.2.4
Divide 0 by 1.
V=π(-42235.241982520+432(17.002915453-0))
V=π(-42235.241982520+432(17.002915453-0))
V=π(-42235.241982520+432(17.002915453-0))
Step 12.2.4.27
Multiply -1 by 0.
V=π(-42235.241982520+432(17.002915453+0))
Step 12.2.4.28
Add 17.002915453 and 0.
V=π(-42235.241982520+432(17.002915453))
Step 12.2.4.29
Combine 432 and 17.002915453.
V=π(-42235.241982520+432⋅17.002915453)
Step 12.2.4.30
Multiply 432 by 17.00291545.
V=π(-42235.241982520+7345.259475213)
Step 12.2.4.31
To write -42235.241982520 as a fraction with a common denominator, multiply by 33.
V=π(-42235.241982520⋅33+7345.259475213)
Step 12.2.4.32
To write 7345.259475213 as a fraction with a common denominator, multiply by 2020.
V=π(-42235.241982520⋅33+7345.259475213⋅2020)
Step 12.2.4.33
Write each expression with a common denominator of 60, by multiplying each by an appropriate factor of 1.
Step 12.2.4.33.1
Multiply 42235.241982520 by 33.
V=π(-42235.2419825⋅320⋅3+7345.259475213⋅2020)
Step 12.2.4.33.2
Multiply 20 by 3.
V=π(-42235.2419825⋅360+7345.259475213⋅2020)
Step 12.2.4.33.3
Multiply 7345.259475213 by 2020.
V=π(-42235.2419825⋅360+7345.25947521⋅203⋅20)
Step 12.2.4.33.4
Multiply 3 by 20.
V=π(-42235.2419825⋅360+7345.25947521⋅2060)
V=π(-42235.2419825⋅360+7345.25947521⋅2060)
Step 12.2.4.34
Combine the numerators over the common denominator.
V=π(-42235.2419825⋅3+7345.25947521⋅2060)
Step 12.2.4.35
Multiply -42235.2419825 by 3.
V=π(-126705.72594752+7345.25947521⋅2060)
Step 12.2.4.36
Multiply 7345.25947521 by 20.
V=π(-126705.72594752+146905.1895043760)
Step 12.2.4.37
Add -126705.72594752 and 146905.18950437.
V=π(20199.4635568560)
Step 12.2.4.38
Combine π and 20199.4635568560.
V=π⋅20199.4635568560
Step 12.2.4.39
Multiply π by 20199.46355685.
V=63458.4863166560
V=63458.4863166560
V=63458.4863166560
V=63458.4863166560
Step 13
Divide 63458.48631665 by 60.
V=1057.64143861
Step 14