Question #4f6e6

1 Answer
Feb 23, 2017

#int(x^6-1)/(1+x^2)dx=1/5x^5-1/3x^3+x-2arctan(x)+C#

Explanation:

Split up the integral:

#I=int(x^6-1)/(1+x^2)dx=intx^6/(1+x^2)dx-intdx/(1+x^2)#

The second is the arctangent integral:

#I=intx^6/(1+x^2)dx-arctan(x)#

Perform long division on what remains, or write the numerator as follows for the same result:

#I=int(x^4(1+x^2)-x^2(1+x^2)+(x^2+1)-1)/(1+x^2)dx-arctan(x)#

Dividing:

#I=intx^4dx-intx^2dx+intdx-intdx/(1+x^2)-arctan(x)#

#I=1/5x^5-1/3x^3+x-2arctan(x)+C#