问题 计算题

计算下列各题(要写出必要的演算步骤.)

(1)(﹣4a5b32÷(8a2b3)÷(﹣53a2);

(2)(x+2)2﹣(x+3)(x﹣3);

(3)[(2x+1)(4x+2)﹣2]÷(﹣8x);

(4)化简、求值:[(2x﹣y)2+(2x+y)(2x﹣y)+8xy]÷2x,其中x=﹣3,y=2.

答案

解:(1)(﹣4a5b32÷(8a2b3)÷(﹣53a2),

=16a10b6÷(8a2b3)÷(﹣53a2),

=2a8b3?(﹣53a2),

=﹣106a10b3

(2)(x+2)2﹣(x+3)(x﹣3),

=(x2+4x+4)﹣(x2﹣9),

=x2+4x+4﹣x2+9,

=4x+13;

(3)[(2x+1)(4x+2)﹣2]÷(﹣8x),

=(8x2+8x+2﹣2)÷(﹣8x),

=(8x2+8x)÷(﹣8x),

=﹣x﹣1;

(4)[(2x﹣y)2+(2x+y)(2x﹣y)+8xy]÷2x,

=(4x2﹣4xy+y2+4x2﹣y2+8xy)÷2x,

=(8x2+4xy)÷2x,

=4x+2y,

当x=﹣3,y=2时,原式=4×(﹣3)+2×2=8.

单项选择题
单项选择题