问题
解答题
计算: (1)(
(2)(-m)2-(m2)2÷m3 (3)-2a2(12ab+b2)-5ab(a2-ab) (4)(4x+3y)(3y-4x)-(4x+3y)2 (5)(x-3y+1)(x+3y-1) (6)(2x+1)2(2x-1)2. |
答案
(1)原式=4-8×0.125+1+1=4-1+1+1=5;
(2)原式=m2•m4÷m3=m3;
(3)原式=-24a3b-2a2b2-5a3b+5a2b2=-29a3b+3a2b2;
(4)原式=9y2-16x2-(16x2+24xy+9y2)=9y2-16x2-16x2-24xy-9y2=-32x2-24xy;
(5)原式=x2-(3y-1)2=x2-9y2+6y-1;
(6)原式=[(2x+1)(2x-1)]2=(4x2-1)2=16x4-8x2+1.