Question

The expression $\frac { ( a + b + c ) ( b + c - a ) } { ( c + a - b ) ( a + b - c ) }$is equal to

• A. $\cos ^ { 2 } \left( \frac { \mathrm {~A} } { 2 } \right)$
• B.
• C. $\cot ^ { 2 } \left( \frac { \mathrm {~A} } { 2 } \right)$
• D.

Answer 1

Answer: (C)

$\cot ^ { 2 } \left( \frac { \mathrm {~A} } { 2 } \right)$

Answer 2

The given expression is equal to