∮cos2x/2 dx
问题描述:
∮cos2x/2 dx
答
设u=2x,du=2dx,原式=cosu*1/4du=1/4cosudu=1/4*sinu=sin2x/4+C答案对不上,大神,我我忘了前面是1-cos2x我提高一下悬赏,你帮我再做一次(1-cos2x)/2 dx?
原式=1/2dx-cos2x/2dx=1/2x-1/2cos2xdx=1/2x-sin2x/4+C=1/2x-sin(2x)/4+C