1/24*(√(5-4x))^3-5/8*√(5-4x)+c 嘿嘿~果然厉害~设√（5-4x）是t x=(5-t^2)/4 dx=-1/2tdt∫x/（√（5-4x））dx=∫(5-t^2)/4t*(-1/2t)dt=∫(t^2-5)/8dt=∫t^2/8dt-∫5/8dt=1/24*t^3-5/8*t+c=1/24*(√(5-4x))^3-5/8*...求过程看上面