问题
解答题
计算:(1)(5a2+2a)-4(2+2a2);
(2)5x2(x+1)(x-1).
答案
(1)(5a2+2a)-4(2+2a2),
=5a2+2a-8-8a2,
=-3a2+2a-8;
(2)5x2(x+1)(x-1),
=5x2(x2-1),
=5x4-5x2.
计算:(1)(5a2+2a)-4(2+2a2);
(2)5x2(x+1)(x-1).
(1)(5a2+2a)-4(2+2a2),
=5a2+2a-8-8a2,
=-3a2+2a-8;
(2)5x2(x+1)(x-1),
=5x2(x2-1),
=5x4-5x2.