Question
Question: In acute angled triangle ABC, r + r<sub>1</sub> = r<sub>2</sub> + r<sub>3</sub> and∠B \>\(\frac { \p...
In acute angled triangle ABC, r + r1 = r2 + r3 and∠B >3π, then
A
b + 2c < 2a < 2b + 2c
B
b + 4c < 4a < 2b + 4c
C
b + 4c < 4a < 4b + 4c
D
b + 3c < 3a < 3b + 3c
Answer
b + 3c < 3a < 3b + 3c
Explanation
Solution
r – r2 = r3 – r1

s(s−b)−b=(s−a)(s−c)−a+c

tan2(B/2) =
But Î(6π,4π)
̃ tan2Î(31,1)
̃ < 1
b < 3a – 3c < 3b
b + 3c < 3a < 3b + 3c