题干

已知 ABAC ,| AB |=
1
t
,| AC |=t,若P点是△ABC所在平面内一点,且 AP =
A
B
|
A
B
|
+
A
C
|
A
C
|
,当t变化时, PBPC 的最大值等于(   )

A:﹣2

B:0

C:2

D:4

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答案(点此获取答案解析)

B

同类题4

阅读材料,回答问题。

材料一:党的十八届五中全会提出“必须牢固树立并切实贯彻创新、协调、绿色、开放、共享的发展理念”。发展理念的提出,对应的是国家富强的发展意志、民族振兴的发展意识、人民幸福的发展宗旨。这五大发展理念,与社会主义核心价值观既一脉相承,又相辅相成,都为我们进一步坚定中国特色社会主义的道路自信、理论自信、制度自信,奠定了重要的政治思想基础和理念基础。我们必须用社会主义核心价值体系引领社会思潮、凝聚社会共识;必须把社会主义核心价值观的培育融入国民教育、精神文明创建活动的全过程,贯穿于社会生活的方方面面,从根本上提高国家文化软实力。

材料二:为切实贯彻“创新、协调、绿色、开放、共事”的发展理念,国务院总理***主持召开国务院常务会议,部署推动医药产业创新升级,更好地惠民生稳增长;确定进一步促进中医药发展措施,发挥传统医学优势造福人民;决定开展服务贸易创新发展试点,推进外贸转型,增强服务业竞争力。2月24日召开的国务院常务会议又确定进一步支持新能源汽车产业的措施,以结构优化推动绿色发展;部署加强文物保护和合理利用,传承文化根脉、凝聚民族精神。

材料三:为了加强文物保护和合理利用。浏阳市大围山镇楚东村,是目前长沙市唯一被列入“国家传统保护村落”的村落。这里人文古迹遍布,国家级文物保护单位锦绶堂,是长沙地区规模最大的清代建筑群。党支部、村委会立足本村实际情况,计划在本村成立一个“传统村落保护与开发协会”的社会组织,以充分挖掘本村丰富的传统村落资源,积极发展文化旅游产业,丰富村民的精神文化生活。

同类题5

阅读下列短文,从每题所给的A、B、C和D项中,选出最佳选项。

I remember, as a kid I had questioned Mom “Why doesn’t Dad love me!” Mom frowned. “Who said he doesn’t love you!” “Well, he never tells me,” I complained. “He never tells me either,”she said, smiling. “But look how hard he works to take care of us, to buy us food and clothes, and to pay for this house. That’s how your father tells us he loves us.”

After Mom died, I began visiting Dad every morning before I went to work. He was frail and moved slowly, but he always had a glass of freshly squeezed orange juice for me. Such a gesture, I knew, was as far as Dad had ever been able to go in expressing his love. Every time after drinking the juice, I walked over, hugged him and said, “I love you, Dad.” My father never told me how he felt about my hugs, and there was never any expression on his face when I gave them.

Then one morning, pressed for time, I drank my juice and made for the door. Dad stepped in front of me and asked, “Well!” “Well what?”I asked, knowing exactly what. “Well!” he repeated, looking everywhere but at me. I hugged him extra hard. It was the right time to say what I’d always wanted to. “I’m fifty years old, Dad, and you’ve never told me you love me.” My father stepped away from me. He picked up the empty juice glass, washed it and put it away. “You’ve told other people you love me.” I said, “but I’ve never heard it from you.” Dad looked very uncomfortable. I moved closer to him. “Dad, I want you to tell me you love me.” Dad took a step back, his lips pressed together. He seemed about to speak, and then shook his head. “Tell me”, I shouted. “All right I love you,” Dad finally blurted. His eyes watered, then overflowed.

I stood before him, stunned and silent. My father loved me so much that just saying so made him weep. Mom had been right. Every day of my life Dad had told me how much he loved me by what he did and what he gave. “I know, Dad,” I said. “I know.” And now at last I did.