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In RT △ ABC, ∠ C = 90 °, AC = 3cm, BC = 4cm, with C as the center, what is the positional relationship between the following r-radius circle and ab? r=2.4cm And R = 3cm
Where is the center of the circle? If the center of the circle is at point C,
When r = 2.4cm, it will be tangent to ab edge
The area of triangle ABC is (BC * AC) / 2 = 6
The area of triangle ABC is (AB * HC) / 2 if the intersection point of a vertical line passing through point C is perpendicular to AB and H
That is, the area of triangle ABC = (BC * AC) / 2 = (AB * HC) / 2 = 6, then ch = 2.4cm can be calculated. When the center of the circle is at point C, r = 2.4cm = HC, then according to the definition of tangent of the circle, we can get "when r = 2.4cm, it will be tangent to ab side"
When r = 3cm, there will be a point on the edge of AB, forming a golden section point
(I'll just give you the conclusion in this part. This calculation needs to be combined with drawing. It's too troublesome. I'm too lazy to do it. I'm sorry.)
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