Question

已知f(x)=e^(-2x) +x/(1+x^2),则∫f(x)dx等于?

Answer 1

∫[e^(-2x)+x/(1+x²)]dx

=(-1/2)∫e^(-2x)d(-2x)+(1/2)∫1/(1+x²)d(1+x²)

=(-1/2)e^(-2x)+(1/2)ln(1+x²)