<Li> s = 2 R + r . (\ displaystyle \ displaystyle s = 2R + r .) </Li> <Li> a 2 + b 2 + c 2 = 8 R 2 . (\ displaystyle \ displaystyle a ^ (2) + b ^ (2) + c ^ (2) = 8R ^ (2).) </Li> <Ul> <Li> A and B are complementary . </Li> <Li> cos ⁡ A cos ⁡ B cos ⁡ C = 0 . (\ displaystyle \ displaystyle \ cos (A) \ cos (B) \ cos (C) = 0 .) </Li> <Li> sin 2 ⁡ A + sin 2 ⁡ B + sin 2 ⁡ C = 2 . (\ displaystyle \ displaystyle \ sin ^ (2) (A) + \ sin ^ (2) (B) + \ sin ^ (2) (C) = 2 .) </Li> <Li> cos 2 ⁡ A + cos 2 ⁡ B + cos 2 ⁡ C = 1 . (\ displaystyle \ displaystyle \ cos ^ (2) (A) + \ cos ^ (2) (B) + \ cos ^ (2) (C) = 1 .) </Li> <Li> sin ⁡ 2 A = sin ⁡ 2 B = 2 sin ⁡ A sin ⁡ B . (\ displaystyle \ displaystyle \ sin (2A) = \ sin (2B) = 2 \ sin (A) \ sin (B).) </Li> </Ul> <Li> A and B are complementary . </Li>

What is the formula for a right triangle