Question

Last question :) ∫tan^-1x dx/1+x^2
Let,tan^-1x=z
or,d/dx tan^-1x=dz/dx
or,1/1+x^2=dz/dx
or,dx/1+x^2=dz
Now,∫tan^-1x dx/1+x^2=∫z.dz=∫z^1dz=z^1+1/1+1+c=z^2/2+c=(tan^-1x)^2/2+c

Answer 1

ofcourse its correct :)

Answer 2

Thank you :)

Answer 3

welcome ^_^

Answer 4

^_^