Trigonometric Identity

[kunal.chanda]

If cosX/cosY = a/b, then atanX + btanY = ?

 

[stapel]

If cosX/cosY = a/b, then atanX + btanY = ?

What have you tried? How far have you gotten? Where are you stuck?

Please be complete. Thank you!

 

[Deleted member 4993]

If cosX/cosY = a/b, then atanX + btanY = ?

Start with:

If \(\displaystyle \dfrac{cos(X)}{cos(Y)} \ = \ \dfrac{a}{b}\)

then

cos(X) = K *a and cos(Y) = K*b (where K is a constant and K\(\displaystyle \ne 0\))

then

sin(X) = ? and sin(Y) = ?

then

tan(X) = ? and tan(Y) = ?

and continue.....