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题目 #184510

UUID
44107256-4d42-4b72-8735-94718283eae8
来源
青岛版/七上/杜辉Q_18951362233_435_检测.pdf 第 2 页,bbox [30.22, 553.94, 556.02, 593.82]
题型 / 学科
subjective / math / JUNIOR
知识树
KT_JUNIOR_MATH_STANDARD
难度
难度 5 / 5 最难 · 复杂推理/计算
QA 状态
PUBLISHED 重试 0 次,得分 0.975
最终题 ID
53115

最终题干渲染(f_body 预览)

观察\(\frac{2}{1 \times 3} = 1\)−\(\frac{1}{3}, \frac{2}{3 \times 5} = \frac{1}{3}\)−\(\frac{1}{5}, \frac{2}{5 \times 7} = \frac{1}{5}\)−\(\frac{1}{7}\)… ,计算\(\frac{2}{1 \times 3} + \frac{2}{3 \times 5} + \frac{2}{5 \times 7} +\)⋯+\(\frac{2}{2023 \times 2025}\)

答案 / 解析

答案(f_answer)

\(\frac{2024}{2025}\)

解析(f_ways)

原式= (1 −\(\frac{1}{3}\)) + (\(\frac{1}{3}\)−\(\frac{1}{5}\)) + ⋯+ (\(\frac{1}{2023}\)−\(\frac{1}{2025}\)) = 1 −\(\frac{1}{2025} = \frac{2024}{2025}\)

原图与资产(0)

该题没有裁出图片资产

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 1.000
SOLVER blind-solver PASS 1.000
CRITIC critic PASS 1.000
SYMBOLIC symbolic-auditor PASS 0.900
COHERENCE coherence-auditor PASS 1.000
QUALITY_GATE quality-gate PASS 0.975

知识点(0)

无

正式题库记录(t_question.f_id=53115)

f_qkey
e45db239413f2e529edc737406f5b44e
f_style / 难度
5 / 2
入库题干
观察\(\frac{2}{1 \times 3} = 1\)−\(\frac{1}{3}, \frac{2}{3 \times 5} = \frac{1}{3}\)−\(\frac{1}{5}, \frac{2}{5 \times 7} = \frac{1}{5}\)−\(\frac{1}{7}\)… ,计算\(\frac{2}{1 \times 3} + \frac{2}{3 \times 5} + \frac{2}{5 \times 7} +\)⋯+\(\frac{2}{2023 \times 2025}\)
入库答案
\(\frac{2024}{2025}\)
入库解析
原式= (1 −\(\frac{1}{3}\)) + (\(\frac{1}{3}\)−\(\frac{1}{5}\)) + ⋯+ (\(\frac{1}{2023}\)−\(\frac{1}{2025}\)) = 1 −\(\frac{1}{2025} = \frac{2024}{2025}\)

事件

时间阶段级别消息
2026-11-11 09:39:08PUBLISHINFO已发布 t_question.f_id=53115 qkey=e45db239413f2e529edc737406f5b44e
2026-11-11 09:39:08QAINFOQA: PASS (score=0.975)
2026-11-11 09:35:19FORMULAWARN公式转换未确认,保留原文本: solution
2026-11-11 09:31:18FORMULAWARN公式转换未确认,保留原文本: answer
2026-11-11 09:27:18FORMULAWARN公式转换未确认,保留原文本: stem