求不定积分∫cos(lnχ)dχ.

admin2017-09-15  47

问题 求不定积分∫cos(lnχ)dχ.

选项

答案I=∫cos(lnχ)dχ[*]∫etcostdt=∫et(sint) =etsint-∫etsintdt=etsint+∫etd(cost)=etsint+etcost-I, 则∫cos(lnχ)dχ=[*]et(sint+cost)+C=[*]sin(lnχ)+cos(lnχ)]+C.

解析
转载请注明原文地址:https://jikaoti.com/ti/IYzRFFFM
0

最新回复(0)