S [1 / (x+4)(x+2)]dx
S [(e/3)的x次方]dx
S {x*[(9x+4)开3次方]}dx
S表示求不定积分，请高手帮忙一下!
也可以给我发消息!谢谢了!
參考答案:1 S [1 / (x+4)(x+2)]dx
=S[1/2(x+2)-1/2(x+4)]dx
=(1/2)*ln(x+2)-(1/2)*ln(x+4)+C
2 S [(e/3)的x次方]dx
=S[e^x*3^(-x)]dx
=e^x*3^(-x)+S[e^x*3^(-x)*ln3]dx
=e^x*3^(-x)+(ln3)*S[e^x*3^(-x)]dx
所以(1-ln3)*S[e^x*3^(-x)]dx=e^x*3^(-x)
S[e^x*3^(-x)]dx=[e^x*3^(-x)]/(1-ln3)+C
3 S {x*[(9x+4)开3次方]}dx
=(3/4)*x*(9x+4)^(4/3)-(3/4)*S[(9x+4)^(4/3)]dx
=(3/4)*x*(9x+4)^(4/3)-(9/28)(9x+4)^(7/3)+C
