题型:综合题
题类:模拟题
难易度:困难
河北省石家庄市长安区2021年中考数学二模试卷
如图1和图2,点
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在数轴上对应的数为16,过原点
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在数轴的上方作射线
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,且
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.点
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从点
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出发,沿数轴以每秒2个单位长度的速度向点
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运动,同时点
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从点
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出发,沿
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方向以每秒1个单位长度的速度运动,当点
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到达点
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时,点
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,
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都停止运动.以点
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为圆心,
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为半径的半圆与数轴正半轴交于点
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,与射线
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交于点
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,连接
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,设运动时间为
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秒
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,点
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在数轴上对应的数为x.
(1)、用含t的式子表示
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的长为
,当点
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与点
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重合时,
;
(2)、若
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与半圆
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相切,求x;
(3)、如图2,当
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时,半圆
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与
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的另一个交点为
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,求
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的度数及
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的长;
(4)、若半圆
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与
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只有一个公共点,直接写出
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的取值范围.