数学化简或计算最后一个是分解因式
1.2√1/2-√x^3+√8x
2.x√x+x√yx+√xy+y
________________________
xy-y^2x√x_y√y
3b-√ab√aba+b
(√a+________)÷(___________+_____________)
√a+√b√ab+b√ab+b√ab
4.x^3_11x^2+31x-21
这是第3个b-√ab√aba+b
(√a+________)÷(___________+_____________)
√a+√b√ab+b√ab+b√ab