中学生网络课堂本课配套习题挑战模式1/5
单选题
难度系数：
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 |
一次做对，真牛！
+5奖励规则>
- 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=
- 答案：QQ==
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
本课配套习题挑战模式2/5
单选题
难度系数：
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 |
一次做对，真牛！
+5奖励规则>
- 提示1：IOagueaNruS4ieinkuW9ouS4reS4iei+ueeahOWFs+ezu++8jOiuoeeul+aWueeoi2I8c3VwPjI8L3N1cD54PHN1cD4yPC9zdXA+K++8iGI8c3VwPjI8L3N1cD4rYzxzdXA+Mjwvc3VwPi1hPHN1cD4yPC9zdXA+77yJeCtjPHN1cD4yPC9zdXA+PTDnmoTilrPnmoTnrKblj7flkI7vvIzliKTmlq3mlrnnqIvnmoTmoLnnmoTmg4XlhrU=
- 答案：Qw==
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本课配套习题挑战模式3/5
单选题
难度系数：
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 |
一次做对，真牛！
+5奖励规则>
- 提示1：IOagueaNruagueeahOWIpOWIq+W8j+eahOaDheWGtei/m+ihjOWIpOaWrQ==
- 答案：Qw==
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
本课配套习题挑战模式4/5
单选题
难度系数：
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 |
一次做对，真牛！
+5奖励规则>
- 提示1：IOKRoCDlsIZiPTJhKzxpbWcgd2lkdGg9NyBoZWlnaHQ9NDIgc3JjPSJodHRwczovL3AyLnFpbmdndW8uY29tL0cxL00wMC83RS9DOS9yQkFDRTFQV0pHRFJiM2NjQUFBQkpEVGxQR1U1MjcucG5nIj5j5Luj5YWl5pa556iL
- 提示2：IOKRoeWIqeeUqGFj77ycMOWSjOagueeahOWIpOWIq+W8j+i/m+ihjOWIpOaWreWNs+WPrw==
- 提示3：IOKRouagueaNruS4gOWFg+S6jOasoeaWueeoi+aIkOeri+eahOadoeS7tuino+etlC4=
- 答案：Qw==
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
本课配套习题挑战模式5/5
单选题
难度系数：
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 |
一次做对，真牛！
+5奖励规则>
- 提示1：IOKRoOKRoeKRo+agueaNruagueeahOWIpOWIq+W8j+WNs+WPr+S9nOWHuuWIpOaWre+8mw==
- 提示2：IOKRouiLpWPmmK/mlrnnqItheDxzdXA+Mjwvc3VwPitieCtjPTDnmoTkuIDkuKrmoLnvvIzliJnku6PlhaXljbPlj6/kvZzlh7rliKTmlq3vvJs=
- 答案：RA==
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
