问题
填空题
⊙O的直径为20,弦AB=8,P是弦AB上的一个动点,则OP的取值范围是______.
答案
最大为半径:20÷2=10;
最小为弦心距:8÷2=4,
弦心距=
=2102-42
,21
所以OP的取值范围是2
≤OP≤10.21
⊙O的直径为20,弦AB=8,P是弦AB上的一个动点,则OP的取值范围是______.
最大为半径:20÷2=10;
最小为弦心距:8÷2=4,
弦心距=
=2102-42
,21
所以OP的取值范围是2
≤OP≤10.21
完形填空。 | |||
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