计算题:
(1)(-2a3b2c)3÷(4a2b3)2-a4c?(-2ac2);
(2)(3x2+4x-1)(3x2-4x-1);
(3);
(4).(n为正整数)
网友回答
解:(1)原式=(-8a9b6c3)÷(16a4b6)+2a5c3
=
=
(2)原式=(3x2-1)2-16x2
=9x4-6x2+1-16x2
=9x4-22x2+1
(3)原式=a3+a2+a-2a2-2a-2+(a2-3)(1-a)
=a3+a2+a-2a2-2a-2+a2-a3-3+3a
=2a-5
(4)原式=16-8+(-0.125)15×815+22n÷22n-2=8+(-0.125×8)15+4=8-1+4=11.
故