DSolve[Derivative[2][y][x] == -((((al1*(-(a2*b1) + a1*b2)*(a3*b1 - a1*b3)*bl1)/(-a1 + b1*x) + (al2*(-(a2*b1) + a1*b2)*(-(a3*b2) + a2*b3)*bl2)/(-a2 + b2*x) + (al3*(a3*b1 - a1*b3)*(-(a3*b2) + a2*b3)*bl3)/(-a3 + b3*x))*y[x])/((-a1 + b1*x)*(-a2 + b2*x)*(-a3 + b3*x))) - ((b1*(1 - al1 - bl1))/(-a1 + b1*x) + (b2*(1 - al2 - bl2))/(-a2 + b2*x) + (b3*(1 - al3 - bl3))/(-a3 + b3*x))*Derivative[1][y][x],y[x],x]