Sum Rule

Reference > Calculus: Integration

Description
f(x)+g(x)dx=f(x)dx+g(x)dx\int f(x)+g(x) \, dx=\int f(x) \, dx+\int g(x) \, dx
Examples
cosx+sinxdx\int \cos{x}+\sin{x} \, dx
1
Use Sum Rule: f(x)+g(x)dx=f(x)dx+g(x)dx\int f(x)+g(x) \, dx=\int f(x) \, dx+\int g(x) \, dx.
cosxdx+sinxdx\int \cos{x} \, dx+\int \sin{x} \, dx

2
Use Trigonometric Integration: the integral of cosx\cos{x} is sinx\sin{x}.
sinx+sinxdx\sin{x}+\int \sin{x} \, dx

3
Use Trigonometric Integration: the integral of sinx\sin{x} is cosx-\cos{x}.
sinxcosx\sin{x}-\cos{x}

4
Add constant.
sinxcosx+C\sin{x}-\cos{x}+C

Done