Question

tan66degree+tan69degree/1-tan66degreetan69degree

Answer 1

Answer:  -1

Step-by-step explanation:

Remember Tan(A+B) = (Tan A + Tan B) / (1 - Tan A * Tan B)

So

Tan 66° + Tan 69° / 1 - [(Tan 66°) * (Tan 69°)]  

= Tan (66° + 69°)

= Tan (135°) = -1.