问题
解答题
化简: (1)2a2-[
(2)多项式x2-xy与另一个整式的和是2x2+xy+3y2,求这一个整式. |
答案
(1)原式=2a2-
ab+1 2
a2-8ab-1 2
ab1 2
=
a2-9ab;5 2
(2)(2x2+xy+3y2)-(x2-xy)
=2x2+xy+3y2-x2+xy
=x2+2xy+3y2.
∴这个整式是x2+2xy+3y2.
化简: (1)2a2-[
(2)多项式x2-xy与另一个整式的和是2x2+xy+3y2,求这一个整式. |
(1)原式=2a2-
ab+1 2
a2-8ab-1 2
ab1 2
=
a2-9ab;5 2
(2)(2x2+xy+3y2)-(x2-xy)
=2x2+xy+3y2-x2+xy
=x2+2xy+3y2.
∴这个整式是x2+2xy+3y2.