题目
把方程x2-3x+p=0配方后,得到(x+m)2=
1 |
2 |
提问时间:2020-06-25
答案
(1)∵x2-3x+p=0,
∴x2-3x=-p,
x2-3x+(
)2=-p+(
)2,
(x-
)2=-p+
,
∴m=-
,-p+
=
,
解得:p=
,m=-
;
(2)∵x2-3x+p=0,
∴(x-
)2=
,
x-
=±
∴x2-3x=-p,
x2-3x+(
3 |
2 |
3 |
2 |
(x-
3 |
2 |
9 |
4 |
∴m=-
3 |
2 |
9 |
4 |
1 |
2 |
解得:p=
7 |
4 |
3 |
2 |
(2)∵x2-3x+p=0,
∴(x-
3 |
2 |
1 |
2 |
x-
3 |
2 |