余弦的3次方的积分,谢谢了
发布网友
发布时间:2022-10-26 15:20
我来回答
共2个回答
热心网友
时间:2023-09-16 21:09
(cosx)^3dx=1-(sinx)^2dsinx=x-(1/3)(sinx)^3+c
热心网友
时间:2023-09-16 21:10
∫cos^3 x dx
=∫cosxcos^2xdx
=∫cosx(1-sin^2)dx
=∫cosxdx-∫cosxsin^2xdx
=-sinx-1/2∫sin2xsinxdx
=-sinx-1/2∫(-1/2(cos(3x)-cosx)dx
=-sinx+1/4*1/3∫cos3xd3x+1/4sinx
=-3/4sinx-1/12sin3x+c
热心网友
时间:2023-09-16 21:09
(cosx)^3dx=1-(sinx)^2dsinx=x-(1/3)(sinx)^3+c
热心网友
时间:2023-09-16 21:10
∫cos^3 x dx
=∫cosxcos^2xdx
=∫cosx(1-sin^2)dx
=∫cosxdx-∫cosxsin^2xdx
=-sinx-1/2∫sin2xsinxdx
=-sinx-1/2∫(-1/2(cos(3x)-cosx)dx
=-sinx+1/4*1/3∫cos3xd3x+1/4sinx
=-3/4sinx-1/12sin3x+c