In a triangle ABC, if 3R = 4r, value of 4(cos A + cos B + cos C) is? (R and r in the triangle have usual notations) Ans: 7 How? I couldn't get 7.
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Originally Posted by fardeen_gen In a triangle ABC, if 3R = 4r, value of 4(cos A + cos B + cos C) is? (R and r in the triangle have usual notations) Ans: 7 How? I couldn't get 7. Please explain what R and r are... Because your usual notations are not necessarily everybody's usual notations...
Hello, moo! Traditionally, these are the accepted definitions . . . . . $\displaystyle R$ is the circumradius, the radius of the circumscribing circle. . . $\displaystyle r$ is the inradius, the radius of the inscribed circle.
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