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

What is the value of the expression?

(tan0° tan1° tan2° tan3° tan4° …… tan89°)

What is the value of $${cos^2A\over {1+sinA}}$$?

The value of $$ {tan\ 40°+tan\ 20° +\sqrt{3}\ tan20° tan40°}$$?

 if $$tan(A+B)=\sqrt { 3} \ $$ and $$ tan(A-B)= {1\over \sqrt { 3} \   }; 0^0<(A+B)<90^0;A>B, $$ then the value of A and B are

Find the value of sec θ − tan θ, if sec θ + tan θ = $$ \sqrt { 5} $$

if $${secA={5\over 4}}$$, then the value of $${{tanA}\over 1+tan^2A}-{sinA\over secA}$$ is

if $$ sinA= {4\over 5}$$, then what is the value of $$sin^2A$$