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题目 #24637

UUID
a0b9171a-236a-4506-9c4a-c1b07bd2c884
来源
人教版/九上/2026江苏九年级期中数学试卷+答案125.pdf 第 2-3 页,bbox [31.56, 782.99, 289.61, 188.68]
题型 / 学科
comprehensive / math / JUNIOR
知识树
KT_JUNIOR_MATH_STANDARD
难度
难度 2 / 5 简单 · 单一知识点
QA 状态
存疑 / 待修复 重试 0 次,得分 0.913
最终题 ID
-
错误
QA failed: COHERENCE,ANSWER

最终题干渲染(f_body 预览)

利用判别式判断下列一元二次方程的根的情况:
Col0 方程,由根的判别式直接 ______________
利用判别式判断下列一元二次方程的根的情况: (1)x2 −3x −7 = 0; (2)9x2 + 6x + 1 = 0; (3)x2 −3√2x + 4 = 0; (4)5x2 + 5x = 4x2 −10. Col1

(1)\(x^{2}\)−3x −7 = 0;
(2)\(9x^{2}\)+ 6x + 1 = 0;
(3)\(x^{2}\)−3√2x + 4 = 0;
(4)\(5x^{2}\)+ 5x =\(4x^{2}\)−10.

答案 / 解析

答案(f_answer)

(1)此方程有两个不等的实数根(2)此方程有两个相等的实数根(3)此方程有两个不等的实数根(4)

解析(f_ways)

此方程无实数根 (1)\(x^{2}\)−3x −7 = 0, ∵a = 1, b = −3, c = −7, ∴\(\Delta =b^{2}\)−4ac = (−3)^{2}−\(4 \times 1\times (−7) = 37\)> 0, ∴ 此方程有两个不等的实数根; (2)\(9x^{2}\)+ 6x + 1 = 0, ∵a = 9, b = 6, c = 1, ∴\(\Delta =b^{2}\)−4ac =\(6^{2}\)−\(4 \times 9 \times 1=0\)∴ 此方程有两个相等的实数根; (3)\(x^{2}\)−3√2x + 4 = 0, ∵a = 1, b = −3√2, c = 4, ∴\(\Delta =b^{2}\)−4ac=(−3√2)^{2}−\(4 \times 1 \times 4 = 2\)> 0, ∴ 此方程有两个不等的实数根; (4)\(5x^{2}\)+ 5x =\(4x^{2}\)−10,\(x^{2}\)+ 5x + 10 = 0, ∵a = 1, b = 5, c = 10, ∴\(\Delta=b^{2}−4ac = 5^{2}−4 \times 1 \times 10 =\)−15 < 0, ∴此方程无实数根.

原图与资产(0)

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审计记录

阶段审计器结果得分依据(简短)
STRUCTURE structure-rule PASS 0.900
FORMULA formula-auditor PASS 1.000
KNOWLEDGE knowledge-auditor WARN -
VISION vision-auditor PASS 0.950
SOLVER blind-solver PASS 1.000
CRITIC critic PASS 1.000
SYMBOLIC symbolic-auditor WARN 0.550
COHERENCE coherence-auditor FAIL 0.800
QUALITY_GATE quality-gate FAIL 0.913
SOLVER blind-solver PASS 1.000
CRITIC critic PASS 1.000
COHERENCE coherence-auditor FAIL 0.900
SYMBOLIC symbolic-auditor PASS 1.000
AUTO_REPAIR_ATTEMPT answer-repair FAIL 1.000

知识点(0)

无

事件

时间阶段级别消息
2026-09-26 02:49:40QA_TERMINALWARNquestion terminal status=QUARANTINED: /data/qbank/quarantine/2b06312b-7e3f-494e-ae3e-21d10207fcf7/question_a0b9171a-236a-4506-9c4a-c1b07bd2c884.json
2026-09-26 02:49:40QAWARNQA: FAIL (score=0.913)
2026-09-26 02:47:51FORMULAWARN公式转换未确认,保留原文本: solution
2026-09-26 02:43:51FORMULAWARN公式转换未确认,保留原文本: sub_4
2026-09-26 02:42:31FORMULAWARN公式转换未确认,保留原文本: sub_3
2026-09-26 02:41:25FORMULAWARN公式转换未确认,保留原文本: sub_2
2026-09-26 02:40:02FORMULAWARN公式转换未确认,保留原文本: sub_1