1 / | | 2 | x *sin(5*x) dx | / 0
Integral(x^2*sin(5*x), (x, 0, 1))
Use integration by parts:
Let and let .
Then .
To find :
Let .
Then let and substitute :
The integral of a constant times a function is the constant times the integral of the function:
The integral of sine is negative cosine:
So, the result is:
Now substitute back in:
Now evaluate the sub-integral.
Use integration by parts:
Let and let .
Then .
To find :
Let .
Then let and substitute :
The integral of a constant times a function is the constant times the integral of the function:
The integral of cosine is sine:
So, the result is:
Now substitute back in:
Now evaluate the sub-integral.
The integral of a constant times a function is the constant times the integral of the function:
Let .
Then let and substitute :
The integral of a constant times a function is the constant times the integral of the function:
The integral of sine is negative cosine:
So, the result is:
Now substitute back in:
So, the result is:
Add the constant of integration:
The answer is:
/ | 2 | 2 2*cos(5*x) x *cos(5*x) 2*x*sin(5*x) | x *sin(5*x) dx = C + ---------- - ----------- + ------------ | 125 5 25 /
2 23*cos(5) 2*sin(5) - --- - --------- + -------- 125 125 25
=
2 23*cos(5) 2*sin(5) - --- - --------- + -------- 125 125 25
-2/125 - 23*cos(5)/125 + 2*sin(5)/25
Use the examples entering the upper and lower limits of integration.