In RT △ ABC, what is the position relationship between the circle with C as the center and R as the radius and ab? （1）r=2cm （2）r=2.5cm （3）r=3cm

Let C be CD ⊥ AB over D. according to different expressions of area, CD * AB = AC * BC, ⊥ CD = 2.4
When (1) r = 2cm, the line AB is away from the circle
(2) When r = 2.5cm, the line AB intersects the circle
(3) When r = 3cm, the line AB intersects the circle
Note: if the relation between line AB and circle is different

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