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As shown in the figure, the circle O is the circumscribed circle of △ ABC, the radius of circle O is 2, SINB = three quarters, then the length of chord AC is
According to the sine theorem B / SINB = 2R, it is obtained that:
AC=b=2RsinB=3
As shown in the figure, ⊙ o is the circumscribed circle of △ ABC, connecting OA and OC, ⊙ O's radius r = 2, SINB = 34, then the length of chord AC is ()
A. 3B. 7C. 32D. 34
Extend the intersection circle of Ao at point D and connect CD. According to the circle angle theorem, it is obtained that: ∠ ACD = 90 °, ∠ d = ∠ B х sind = SINB = 34, in RT △ ADC, sind = 34, ad = 2R = 4, х AC = ad · sind = 3
Circle is the circumscribed circle of triangle ABC, radius of circle r = 2, SINB = 3 / 4, then how long is dazzle AC?
This problem investigates the sine theorem
A / Sina = B / SINB = C / sinc = 2R (R is the radius of circumscribed circle)
So AC / SINB = 2R, that is, AC / (3 / 4) = 2 * 2, so AC = 3
The circle is the circumscribed circle of triangle ABC, the radius of the circle r = 2, SINB = 3 / 4, then how long is the dazzle AC
Please use the knowledge of grade three to solve the problem. Of course, let me see the Zhengxuan theorem. At that time, we should also use the knowledge of grade three to solve the problem
Make diameter ad connection CD, ∠ B = ∠ D, ad = 4
In ACD, SINB = AC / ad = 3 / 4 = SINB
AC=3
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