问题
解答题
计算: (1)3x2+1+2x-5+3x-2x2 (2)
(3)3x2-[7x-(4x-3)-2x2]. |
答案
(1)原式=x2+5x-4;
(2)原式=
x-2x+1 2
y2-2 3
x+3 2
y21 3
=-3x+y2;
(3)原式=3x2-7x+4x-3+2x2
=5x2-3x-3.
计算: (1)3x2+1+2x-5+3x-2x2 (2)
(3)3x2-[7x-(4x-3)-2x2]. |
(1)原式=x2+5x-4;
(2)原式=
x-2x+1 2
y2-2 3
x+3 2
y21 3
=-3x+y2;
(3)原式=3x2-7x+4x-3+2x2
=5x2-3x-3.