AP EAMCET202123 Aug 2021Evening ShiftMathematicsProperties of TrianglesActual
In A B C, 16 R s A 2 B 2 C 2 s-c is equal to
Options
- Ar₁ r₂ r₃
- Br₁ r₂ r₃
- Cr₁+r₂+r₃
- D4 r₁ r₂ r₃
Correct answer
D. 4 r₁ r₂ r₃
Step-by-step solution
In A B C, A+B+C= ...(i) When A, B, C are the angles of A B C . Let R be the circumradius and s be semiperimeter and be the area of A B C 16 R s A 2 B 2 C 2 s-c = (4 R )(4 s) s-c (s-b)(s-c) b c (s-a)(s-c) a c s(s-c) a b A 2 = (s-b)(s-c) b c , B 2 = (s-a)(s-c) a c C 2 = s(s-c) a b r₁= s-a , r₂= s-b , r₃= s-c aligned & and = a b c 4 R & or 4 R =a b c aligned aligned & = (a b c)(4 s) s-c (s-c) s(s-a)(s-b)(s-c) a b c & =4 s aligned aligned & = 4 s ^3 ^2 = 4 s ^3 s(s-a)(s-b)(s-c) & =4 s-a s-b s-c aligned =4 r₁ r₂ r₃