原式=2x^2-2-4+2(x^2+x-2)
=2x^2-6+2x^2+2x-4
=4x^2+2x-10
=1+1-10
=-8
数学七下方程计算题
数学七下方程计算题
先计算再求值2(x^2-1)-[4-2(x+2)(x-1)],其中x=二分之一
先计算再求值2(x^2-1)-[4-2(x+2)(x-1)],其中x=二分之一
数学人气:150 ℃时间:2020-05-04 06:42:55
优质解答
我来回答
类似推荐
猜你喜欢
- 1人间永远有真情写一篇作文
- 2x1,x2是x^2-2003x+2005=0根ab满足ax1^2003+bx2^2003=2003,ax1^2004+bx2^2004=2004.求ax1^2005+bx2^2005=
- 3Tom has been writing letters all afternoon,but he should have finished them by now,______?
- 4what is it about?tell me________
- 5现要测定某溶液的pH,使用pH试纸,若事先用水把试纸润湿再测pH,则实际测得值与真实值比较( ) A.变大 B.变小 C.不变 D.无法确定
- 6(x2-5)2+8(x2-5)+16怎么因式分解
- 7高一中文修辞造句,请各位大大帮帮小弟!
- 8I can't do it I help you?
- 9改错No sooner the girl heard the sad news than she burst out crying说理由
- 10需要一篇关于edgar allan poe的论文