Question

Without using trigonometric tables, prove that:

tan²66° − cot²24° = 0

Answer 1

LHS = tan²66° − cot²24°

 = tan² (`90^circ - 24^circ`) - cot²`24^circ`

 = cot² `24^circ` - cot² `24^circ`

= 0

= RHS