what is the value of the expression
 cos 2A cos2B+sin²(A-B)-sin²(A+B)?

Find the exact value of cos 120⁰.

What is the value of cosecA(1 − cosA)(cosecA + cotA)?

If x = a secθ cos∅, y = b secθ sin∅, z=c tanθ, then the value of $$ {x^2\over a^2}+{y^2\over b^2}-{z^2\over c^2} $$

If $${secθ+tanθ\over secθ-tanθ}={5\over 3}$$ then sinθ is equal to ;

$$\left({1\over cosecθ}-{1\over sinθ} \right)+{1\over {cosecθ-cotθ}} -{1\over secθ+tanθ} =?$$

Find the value of tan 27⁰ tan34⁰ + tan34⁰ tan29⁰ + tan29⁰ tan27⁰.

△ABC is right-angle triangle at B and tan A = $$3\over 4$$, then sin A + sin B + sin C will be equal to: