一题：求[x^2/sqrt(x-x^2)]dx的积分3 arc sin(2x-1)/8 + (-x/2-3/4)*Sqrt(-x(x-1))二题：求[(x^2+x+1)/(x+1)^50]dx的积分 -(1176*x^2+49x+1129)/(55272*(x+1)^49)三题：求[(tanX)^4]dX的积分3x*((cos x)^3-3sinx(cos...