1/5单选题
难度：
1.下列方程中有两个相等实数根的是（ ）
| A | x2+2x+1=0 |
| B | 2x2-4x+4=0 |
| C | （x-1）2=-4 |
| D | 5x2+4x=1 |
- 提示1：
- IOaKiuaWueeoi+mDveWPmOW9ouS4uuS4gOWFg+S6jOasoeaWueeoi+eahOS4gOiIrOW8jzs=
- 提示2：
- IOWGjeWIhuWIq+iuoeeul+WIpOWIq+W8j+KWsz1iPHN1cD4yPC9zdXA+LTRhYzs=
- 提示3：
- IOeEtuWQjuWIhuWIq+agueaNruKWs+eahOaEj+S5iei/m+ihjOWIpOaWreWNs+WPry4=
正确答案：QQ==
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
2/5单选题
难度：
2.已知a，b，c是三角形三条边的长，则：方程b2x2+（b2+c2-a2）x+c2=0的根的情况为（ ）无实数根.
| A | 两个不等实根 |
| B | 两个相等实根 |
| C | 无实数根 |
| D | 无法判断 |
- 提示1：
- IOagueaNruS4ieinkuW9ouS4reS4iei+ueeahOWFs+ezu++8jOiuoeeul+aWueeoi2I8c3VwPjI8L3N1cD54PHN1cD4yPC9zdXA+K++8iGI8c3VwPjI8L3N1cD4rYzxzdXA+Mjwvc3VwPi1hPHN1cD4yPC9zdXA+77yJeCtjPHN1cD4yPC9zdXA+PTDnmoTilrPnmoTnrKblj7flkI7vvIzliKTmlq3mlrnnqIvnmoTmoLnnmoTmg4XlhrU=
正确答案：Qw==
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
3/5单选题
难度：
3.对关于x的方程ax2+bx+c=0（a≠0）. 下列结论中：
①方程的解为x＝
；②若a+c=0，方程ax2+bx+c=0有两个不等的实数根；③若方程ax2+bx+c=0有两个不等的实数根，则方程x2+bx+ac=0也一定有两个不等的实数根；④若二次三项式ax2+bx+c是完全平方式，则方程ax2+bx+c=0必有两相等实根；其中正确的结论是（ ）
①方程的解为x＝
；②若a+c=0，方程ax2+bx+c=0有两个不等的实数根；③若方程ax2+bx+c=0有两个不等的实数根，则方程x2+bx+ac=0也一定有两个不等的实数根；④若二次三项式ax2+bx+c是完全平方式，则方程ax2+bx+c=0必有两相等实根；其中正确的结论是（ ） | A | ①③④ |
| B | ①②④ |
| C | ②③④ |
| D | ①②③ |
- 提示1：
- IOagueaNruagueeahOWIpOWIq+W8j+eahOaDheWGtei/m+ihjOWIpOaWrQ==
正确答案：Qw==
6Kej77ya4pGg6Iul4pazPWI8c3VwPjI8L3N1cD4tNGFj77ycMO+8jOWImeaWueeoi+ayoeacieWunuaVsOino++8jOaVheacrOWwj+mimOmUmeivr++8mzxicj7ikaHiiLVhK2M9MO+8jDxicj7iiLRjPS1h77yMPGJyPuKItOKWsz1iPHN1cD4yPC9zdXA+LTRhYz1iPHN1cD4yPC9zdXA+LTRh77yILWHvvIk9YjxzdXA+Mjwvc3VwPis0YTxzdXA+Mjwvc3VwPu+8jDxicj7iiLViPHN1cD4yPC9zdXA+4omlMO+8jDRhPHN1cD4yPC9zdXA+77yeMO+8jDxicj7iiLTilrPvvJ4w77yMPGJyPuKItOaWueeoi2F4PHN1cD4yPC9zdXA+K2J4K2M9MOacieS4pOS4quS4jeetieeahOWunuaVsOague+8jOaVheacrOWwj+mimOato+ehru+8mzxicj7ikaLiiLXmlrnnqItheDxzdXA+Mjwvc3VwPitieCtjPTDmnInkuKTkuKrkuI3nrYnnmoTlrp7mlbDmoLnvvIw8YnI+4oi04pazPWI8c3VwPjI8L3N1cD4tNGFj77yeMO+8jDxicj7mlrnnqIt4PHN1cD4yPC9zdXA+K2J4K2FjPTDnmoTilrM9YjxzdXA+Mjwvc3VwPi00YWPvvJ4w77yMPGJyPuKItOaWueeoi3g8c3VwPjI8L3N1cD4rYngrYWM9MOS5n+S4gOWumuacieS4pOS4quS4jeetieeahOWunuaVsOague+8jOaVheacrOWwj+mimOato+ehru+8mzxicj7ikaPiiLXkuozmrKHkuInpobnlvI9heDxzdXA+Mjwvc3VwPitieCtj5piv5a6M5YWo5bmz5pa55byP77yMPGJyPuKItGI9MjxpbWcgd2lkdGg9MjUgaGVpZ2h0PTIxIHNyYz0iaHR0cHM6Ly9wMi5xaW5nZ3VvLmNvbS9HMS9NMDAvN0UvQzgvckJBQ0UxUFdKRmZBTVNiYUFBQUJrRXlsazFZMTk1LnBuZyI+77yM4oi04pazPWI8c3VwPjI8L3N1cD4tNGFjPWI8c3VwPjI8L3N1cD4tNMOXPGltZyB3aWR0aD02IGhlaWdodD00MiBzcmM9Imh0dHBzOi8vcDEucWluZ2d1by5jb20vRzEvTTAwLzQxLzczL3JCQUNGRlBXSkZpd1BxeTZBQUFCS1dxYzV2TTU3Ny5wbmciPmI8c3VwPjI8L3N1cD49MO+8jDxicj7iiLTmlrnnqItheDxzdXA+Mjwvc3VwPitieCtjPTDlv4XmnInkuKTnm7jnrYnlrp7moLnvvIzmlYXmnKzlsI/popjmraPnoa7vvIw8YnI+57u85LiK5omA6L+w77yM5q2j56Gu55qE57uT6K665piv4pGh4pGi4pGjLiA8YnI+5pWF6YCJQy4gPHRhYmxlIGNsYXNzPU1zb05vcm1hbFRhYmxlIGJvcmRlcj0wIGNlbGxzcGFjaW5nPTAgY2VsbHBhZGRpbmc9MCBzdHlsZT0nYm9yZGVyLWNvbGxhcHNlOmNvbGxhcHNlJz4gPHRyPiAgPHRkIHN0eWxlPSdwYWRkaW5nOi0uNzVwdCAtLjc1cHQgLS43NXB0IC0uNzVwdCc+PC90ZD4gPC90cj48L3RhYmxlPg==
4/5单选题
难度：
4.下列命题：
①若b=2a+
c，则一元二次方程ax2+bx+c=O必有一根为-2；
②若ac＜0，则方程cx2+bx+a=O有两个不等实数根；
③若b2-4ac=0，则方程cx2+bx+a=O有两个相等实数根；
其中正确的个数是（ ）
①若b=2a+
c，则一元二次方程ax2+bx+c=O必有一根为-2；②若ac＜0，则方程cx2+bx+a=O有两个不等实数根；
③若b2-4ac=0，则方程cx2+bx+a=O有两个相等实数根；
其中正确的个数是（ ）
| A | 0个 |
| B | 1个 |
| C | 2个 |
| D | 3个 |
- 提示1：
- IOKRoCDlsIZiPTJhKzxpbWcgd2lkdGg9NyBoZWlnaHQ9NDIgc3JjPSJodHRwczovL3AyLnFpbmdndW8uY29tL0cxL00wMC83RS9DOS9yQkFDRTFQV0pHRFJiM2NjQUFBQkpEVGxQR1U1MjcucG5nIj5j5Luj5YWl5pa556iL
- 提示2：
- IOKRoeWIqeeUqGFj77ycMOWSjOagueeahOWIpOWIq+W8j+i/m+ihjOWIpOaWreWNs+WPrw==
- 提示3：
- IOKRouagueaNruS4gOWFg+S6jOasoeaWueeoi+aIkOeri+eahOadoeS7tuino+etlC4=
正确答案：Qw==
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
5/5单选题
难度：
5.对于一元二次方程ax2+bx+c=0（a≠0），下列说法：
①若a+c=0，方程ax2+bx+c=0有两个不等的实数根；
②若方程ax2+bx+c=0有两个不等的实数根，则方程cx2+bx+a=0也一定有两个不等的实数根；
③若c是方程ax2+bx+c=0的一个根，则一定有ac+b+1=0成立；
④若m是方程ax2+bx+c=0的一个根，则一定有b2-4ac=（2am+b）2成立.
其中正确地只有（ ）
①若a+c=0，方程ax2+bx+c=0有两个不等的实数根；
②若方程ax2+bx+c=0有两个不等的实数根，则方程cx2+bx+a=0也一定有两个不等的实数根；
③若c是方程ax2+bx+c=0的一个根，则一定有ac+b+1=0成立；
④若m是方程ax2+bx+c=0的一个根，则一定有b2-4ac=（2am+b）2成立.
其中正确地只有（ ）
| A | ①② |
| B | ②③ |
| C | ③④ |
| D | ①④ |
- 提示1：
- IOKRoOKRoeKRo+agueaNruagueeahOWIpOWIq+W8j+WNs+WPr+S9nOWHuuWIpOaWre+8mw==
- 提示2：
- IOKRouiLpWPmmK/mlrnnqItheDxzdXA+Mjwvc3VwPitieCtjPTDnmoTkuIDkuKrmoLnvvIzliJnku6PlhaXljbPlj6/kvZzlh7rliKTmlq3vvJs=
正确答案：RA==
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