令x^2=sinu,则:u=arcsin(x^2),2xdx=cosudu。
∴∫[x/(1-x^4)^(3/2)]dx
=(1/2)∫{1/[1-(sinu)^2]^(3/2)}cosudu
=(1/2)∫{1/[(cosu)^2]^(3/2)}cosudu
=(1/2)∫[1/(cosu)^3]cosudu
=(1/2)∫[1/(cosu)^2]du
=(1/2)tanu+C
=(1/2)tan[arcsin(x^2)]+C
=(1/2)sin[arcsin(x^2)]/√{1-[arcsin(x^2)]^2}+C
=(1/2)x^2/√(1-x^4)+C