Integral of sin(5*x)*sin(3*x) dx
The solution
Detail solution
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Rewrite the integrand:
sin(3x)sin(5x)=−64sin8(x)+128sin6(x)−80sin4(x)+15sin2(x)
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Integrate term-by-term:
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The integral of a constant times a function is the constant times the integral of the function:
∫(−64sin8(x))dx=−64∫sin8(x)dx
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Rewrite the integrand:
sin8(x)=(21−2cos(2x))4
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There are multiple ways to do this integral.
Method #1
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Rewrite the integrand:
(21−2cos(2x))4=16cos4(2x)−4cos3(2x)+83cos2(2x)−4cos(2x)+161
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫16cos4(2x)dx=16∫cos4(2x)dx
-
Rewrite the integrand:
cos4(2x)=(2cos(4x)+21)2
-
Rewrite the integrand:
(2cos(4x)+21)2=4cos2(4x)+2cos(4x)+41
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫4cos2(4x)dx=4∫cos2(4x)dx
-
Rewrite the integrand:
cos2(4x)=2cos(8x)+21
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫2cos(8x)dx=2∫cos(8x)dx
-
Let u=8x.
Then let du=8dx and substitute 8du:
∫8cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=8∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 8sin(u)
Now substitute u back in:
8sin(8x)
So, the result is: 16sin(8x)
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The integral of a constant is the constant times the variable of integration:
∫21dx=2x
The result is: 2x+16sin(8x)
So, the result is: 8x+64sin(8x)
-
The integral of a constant times a function is the constant times the integral of the function:
∫2cos(4x)dx=2∫cos(4x)dx
-
Let u=4x.
Then let du=4dx and substitute 4du:
∫4cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=4∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 4sin(u)
Now substitute u back in:
4sin(4x)
So, the result is: 8sin(4x)
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The integral of a constant is the constant times the variable of integration:
∫41dx=4x
The result is: 83x+8sin(4x)+64sin(8x)
So, the result is: 1283x+128sin(4x)+1024sin(8x)
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The integral of a constant times a function is the constant times the integral of the function:
∫(−4cos3(2x))dx=−4∫cos3(2x)dx
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Rewrite the integrand:
cos3(2x)=(1−sin2(2x))cos(2x)
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There are multiple ways to do this integral.
Method #1
-
Let u=sin(2x).
Then let du=2cos(2x)dx and substitute du:
∫(21−2u2)du
-
Integrate term-by-term:
-
The integral of a constant is the constant times the variable of integration:
∫21du=2u
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−2u2)du=−2∫u2du
-
The integral of un is n+1un+1 when n=−1:
∫u2du=3u3
So, the result is: −6u3
The result is: −6u3+2u
Now substitute u back in:
−6sin3(2x)+2sin(2x)
Method #2
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Rewrite the integrand:
(1−sin2(2x))cos(2x)=−sin2(2x)cos(2x)+cos(2x)
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Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−sin2(2x)cos(2x))dx=−∫sin2(2x)cos(2x)dx
-
Let u=sin(2x).
Then let du=2cos(2x)dx and substitute 2du:
∫2u2du
-
The integral of a constant times a function is the constant times the integral of the function:
∫u2du=2∫u2du
-
The integral of un is n+1un+1 when n=−1:
∫u2du=3u3
So, the result is: 6u3
Now substitute u back in:
6sin3(2x)
So, the result is: −6sin3(2x)
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Let u=2x.
Then let du=2dx and substitute 2du:
∫2cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=2∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 2sin(u)
Now substitute u back in:
2sin(2x)
The result is: −6sin3(2x)+2sin(2x)
Method #3
-
Rewrite the integrand:
(1−sin2(2x))cos(2x)=−sin2(2x)cos(2x)+cos(2x)
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−sin2(2x)cos(2x))dx=−∫sin2(2x)cos(2x)dx
-
Let u=sin(2x).
Then let du=2cos(2x)dx and substitute 2du:
∫2u2du
-
The integral of a constant times a function is the constant times the integral of the function:
∫u2du=2∫u2du
-
The integral of un is n+1un+1 when n=−1:
∫u2du=3u3
So, the result is: 6u3
Now substitute u back in:
6sin3(2x)
So, the result is: −6sin3(2x)
-
Let u=2x.
Then let du=2dx and substitute 2du:
∫2cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=2∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 2sin(u)
Now substitute u back in:
2sin(2x)
The result is: −6sin3(2x)+2sin(2x)
So, the result is: 24sin3(2x)−8sin(2x)
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The integral of a constant times a function is the constant times the integral of the function:
∫83cos2(2x)dx=83∫cos2(2x)dx
-
Rewrite the integrand:
cos2(2x)=2cos(4x)+21
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫2cos(4x)dx=2∫cos(4x)dx
-
Let u=4x.
Then let du=4dx and substitute 4du:
∫4cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=4∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 4sin(u)
Now substitute u back in:
4sin(4x)
So, the result is: 8sin(4x)
-
The integral of a constant is the constant times the variable of integration:
∫21dx=2x
The result is: 2x+8sin(4x)
So, the result is: 163x+643sin(4x)
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−4cos(2x))dx=−4∫cos(2x)dx
-
Let u=2x.
Then let du=2dx and substitute 2du:
∫2cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=2∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 2sin(u)
Now substitute u back in:
2sin(2x)
So, the result is: −8sin(2x)
-
The integral of a constant is the constant times the variable of integration:
∫161dx=16x
The result is: 12835x+24sin3(2x)−4sin(2x)+1287sin(4x)+1024sin(8x)
Method #2
-
Rewrite the integrand:
(21−2cos(2x))4=16cos4(2x)−4cos3(2x)+83cos2(2x)−4cos(2x)+161
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫16cos4(2x)dx=16∫cos4(2x)dx
-
Rewrite the integrand:
cos4(2x)=(2cos(4x)+21)2
-
Rewrite the integrand:
(2cos(4x)+21)2=4cos2(4x)+2cos(4x)+41
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫4cos2(4x)dx=4∫cos2(4x)dx
-
Rewrite the integrand:
cos2(4x)=2cos(8x)+21
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫2cos(8x)dx=2∫cos(8x)dx
-
Let u=8x.
Then let du=8dx and substitute 8du:
∫8cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=8∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 8sin(u)
Now substitute u back in:
8sin(8x)
So, the result is: 16sin(8x)
-
The integral of a constant is the constant times the variable of integration:
∫21dx=2x
The result is: 2x+16sin(8x)
So, the result is: 8x+64sin(8x)
-
The integral of a constant times a function is the constant times the integral of the function:
∫2cos(4x)dx=2∫cos(4x)dx
-
Let u=4x.
Then let du=4dx and substitute 4du:
∫4cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=4∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 4sin(u)
Now substitute u back in:
4sin(4x)
So, the result is: 8sin(4x)
-
The integral of a constant is the constant times the variable of integration:
∫41dx=4x
The result is: 83x+8sin(4x)+64sin(8x)
So, the result is: 1283x+128sin(4x)+1024sin(8x)
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−4cos3(2x))dx=−4∫cos3(2x)dx
-
Rewrite the integrand:
cos3(2x)=(1−sin2(2x))cos(2x)
-
Let u=sin(2x).
Then let du=2cos(2x)dx and substitute du:
∫(21−2u2)du
-
Integrate term-by-term:
-
The integral of a constant is the constant times the variable of integration:
∫21du=2u
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−2u2)du=−2∫u2du
-
The integral of un is n+1un+1 when n=−1:
∫u2du=3u3
So, the result is: −6u3
The result is: −6u3+2u
Now substitute u back in:
−6sin3(2x)+2sin(2x)
So, the result is: 24sin3(2x)−8sin(2x)
-
The integral of a constant times a function is the constant times the integral of the function:
∫83cos2(2x)dx=83∫cos2(2x)dx
-
Rewrite the integrand:
cos2(2x)=2cos(4x)+21
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫2cos(4x)dx=2∫cos(4x)dx
-
Let u=4x.
Then let du=4dx and substitute 4du:
∫4cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=4∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 4sin(u)
Now substitute u back in:
4sin(4x)
So, the result is: 8sin(4x)
-
The integral of a constant is the constant times the variable of integration:
∫21dx=2x
The result is: 2x+8sin(4x)
So, the result is: 163x+643sin(4x)
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−4cos(2x))dx=−4∫cos(2x)dx
-
Let u=2x.
Then let du=2dx and substitute 2du:
∫2cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=2∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 2sin(u)
Now substitute u back in:
2sin(2x)
So, the result is: −8sin(2x)
-
The integral of a constant is the constant times the variable of integration:
∫161dx=16x
The result is: 12835x+24sin3(2x)−4sin(2x)+1287sin(4x)+1024sin(8x)
So, the result is: −235x−38sin3(2x)+16sin(2x)−27sin(4x)−16sin(8x)
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The integral of a constant times a function is the constant times the integral of the function:
∫128sin6(x)dx=128∫sin6(x)dx
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Rewrite the integrand:
sin6(x)=(21−2cos(2x))3
-
Rewrite the integrand:
(21−2cos(2x))3=−8cos3(2x)+83cos2(2x)−83cos(2x)+81
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−8cos3(2x))dx=−8∫cos3(2x)dx
-
Rewrite the integrand:
cos3(2x)=(1−sin2(2x))cos(2x)
-
Let u=sin(2x).
Then let du=2cos(2x)dx and substitute du:
∫(21−2u2)du
-
Integrate term-by-term:
-
The integral of a constant is the constant times the variable of integration:
∫21du=2u
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−2u2)du=−2∫u2du
-
The integral of un is n+1un+1 when n=−1:
∫u2du=3u3
So, the result is: −6u3
The result is: −6u3+2u
Now substitute u back in:
−6sin3(2x)+2sin(2x)
So, the result is: 48sin3(2x)−16sin(2x)
-
The integral of a constant times a function is the constant times the integral of the function:
∫83cos2(2x)dx=83∫cos2(2x)dx
-
Rewrite the integrand:
cos2(2x)=2cos(4x)+21
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫2cos(4x)dx=2∫cos(4x)dx
-
Let u=4x.
Then let du=4dx and substitute 4du:
∫4cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=4∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 4sin(u)
Now substitute u back in:
4sin(4x)
So, the result is: 8sin(4x)
-
The integral of a constant is the constant times the variable of integration:
∫21dx=2x
The result is: 2x+8sin(4x)
So, the result is: 163x+643sin(4x)
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−83cos(2x))dx=−83∫cos(2x)dx
-
Let u=2x.
Then let du=2dx and substitute 2du:
∫2cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=2∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 2sin(u)
Now substitute u back in:
2sin(2x)
So, the result is: −163sin(2x)
-
The integral of a constant is the constant times the variable of integration:
∫81dx=8x
The result is: 165x+48sin3(2x)−4sin(2x)+643sin(4x)
So, the result is: 40x+38sin3(2x)−32sin(2x)+6sin(4x)
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−80sin4(x))dx=−80∫sin4(x)dx
-
Rewrite the integrand:
sin4(x)=(21−2cos(2x))2
-
Rewrite the integrand:
(21−2cos(2x))2=4cos2(2x)−2cos(2x)+41
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫4cos2(2x)dx=4∫cos2(2x)dx
-
Rewrite the integrand:
cos2(2x)=2cos(4x)+21
-
Integrate term-by-term:
-
The integral of a constant times a function is the constant times the integral of the function:
∫2cos(4x)dx=2∫cos(4x)dx
-
Let u=4x.
Then let du=4dx and substitute 4du:
∫4cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=4∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 4sin(u)
Now substitute u back in:
4sin(4x)
So, the result is: 8sin(4x)
-
The integral of a constant is the constant times the variable of integration:
∫21dx=2x
The result is: 2x+8sin(4x)
So, the result is: 8x+32sin(4x)
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−2cos(2x))dx=−2∫cos(2x)dx
-
Let u=2x.
Then let du=2dx and substitute 2du:
∫2cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=2∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 2sin(u)
Now substitute u back in:
2sin(2x)
So, the result is: −4sin(2x)
-
The integral of a constant is the constant times the variable of integration:
∫41dx=4x
The result is: 83x−4sin(2x)+32sin(4x)
So, the result is: −30x+20sin(2x)−25sin(4x)
-
The integral of a constant times a function is the constant times the integral of the function:
∫15sin2(x)dx=15∫sin2(x)dx
-
Rewrite the integrand:
sin2(x)=21−2cos(2x)
-
Integrate term-by-term:
-
The integral of a constant is the constant times the variable of integration:
∫21dx=2x
-
The integral of a constant times a function is the constant times the integral of the function:
∫(−2cos(2x))dx=−2∫cos(2x)dx
-
Let u=2x.
Then let du=2dx and substitute 2du:
∫2cos(u)du
-
The integral of a constant times a function is the constant times the integral of the function:
∫cos(u)du=2∫cos(u)du
-
The integral of cosine is sine:
∫cos(u)du=sin(u)
So, the result is: 2sin(u)
Now substitute u back in:
2sin(2x)
So, the result is: −4sin(2x)
The result is: 2x−4sin(2x)
So, the result is: 215x−415sin(2x)
The result is: 4sin(2x)−16sin(8x)
-
Add the constant of integration:
4sin(2x)−16sin(8x)+constant
The answer is:
4sin(2x)−16sin(8x)+constant
The answer (Indefinite)
[src]
/
| sin(8*x) sin(2*x)
| sin(5*x)*sin(3*x) dx = C - -------- + --------
| 16 4
/
∫sin(3x)sin(5x)dx=C+4sin(2x)−16sin(8x)
The graph
5*cos(5)*sin(3) 3*cos(3)*sin(5)
- --------------- + ---------------
16 16
−165sin(3)cos(5)+163sin(5)cos(3)
=
5*cos(5)*sin(3) 3*cos(3)*sin(5)
- --------------- + ---------------
16 16
−165sin(3)cos(5)+163sin(5)cos(3)
-5*cos(5)*sin(3)/16 + 3*cos(3)*sin(5)/16
Use the examples entering the upper and lower limits of integration.