Question

微积分题目谢谢谢谢

希望有详细过程，谢谢🙏

Answer 1

∫x^2sinxdx
=-∫x^2d(cosx)
=-x^2cosx + ∫cosxd(x^2)
=-x^2cosx + ∫2xcosxdx
=-x^2cosx + 2∫xd(sinx)
=-x^2cosx + 2(xsinx -∫sinxdx)
=-x^2cosx + 2xsinx + 2cosx + C
∫ xarcsinx dx
= ∫ arcsinx d(x²/2)
= (1/2)x²arcsinx - (1/2)∫ x²/√(1 - x²) dx,x = sinz
= (1/2)x²arcsinx - (1/2)∫ sin²z/|cosz| * (cosz dz)
= (1/2)x²arcsinx - (1/2)∫ (1 - cos2z)/2 dz
= (1/2)x²arcsinx - (1/4)(z - 1/2*sin2z) + C
= (1/2)x²arcsinx - (1/4)arcsinx + (1/4)x√(1 - x²) + C
∫ arctanx dx
=xarctanx-∫ x/(1+x²)dx
=xarctanx-1/2∫ 1/(1+x²)d(x²)
=xarctanx-(1/2)ln(x²+1)+C
∫lnx/x^2dx
=-∫lnxd(1/x)
=-lnx/x+∫(1/x)dlnx
=-lnx/x+∫1/x² dx
=-lnx/x-1/x+C
哥们有点多哦，建议每次提问只问一个问题

Answer 2