如题所述
â«xâ§5sinx²dx
=1/2â«x⁴sinx²dx²
=-1/2â«x⁴dcosx²
=-x⁴cosx²/2+1/2â«cosx²dx⁴
=-x⁴cosx²/2+â«x²cosx²dx²
=-x⁴cosx²/2+â«x²dsinx²
=-x⁴cosx²/2+x²dsinx²-â«sinx²dx²
=-x⁴cosx²/2+x²dsinx²-cosx²+C