题目内容
先化简，再求值：
．其中
满足一元二次方程
．
解：
=
······························································································· 2分
=
··························································································· 3分
=
=
．··············································································································· 5分
化简方程 得：
，··················································································································· 6分
解得
，
．·········································································································· 8分
因为当时原式无意义，所以舍去； ··············································································· 9分
当时，原式=
．··························································································· 10分
出彩同步大试卷系列答案
，则底角为 ．
B．
C．
D．
，则这个正六边形的面积为 cm2．
倍，且每天包装大黄米和江米的质量之和为45千克．
少千克?
质量．分别求出在这20天内每天包装大黄米和江米的质量随天数变化的函数关系式，并写出自变量的取值范围．
下列运算正确的是（ ）
|
| A． | a6÷a2=a3 | B． | （a+b）2=a2+b2 | C． | 2﹣3=﹣6 | D． |
|
=﹣3
