In the given figure BC=15 cm and Sin B=4/5.  then find out the value of AB?

If $$ {cot A={n\over{n+1}}}$$ and $$ {cot B={1\over{2n+1}}}$$ then what is the value of cot (A + B)?

If 1 + sin² A = 3 sin A cos A, then what are the possible values of tan A?

Find the value of $$ {\sqrt{(cos^{2}20°+cos^{2}70°)}}$$

In ΔABC θ is an acute angle and tanθ is equal to three times of cotθ. Find the value of $$ {sin^{2}θ+cosec^{2}θ-{1\over 2}cot^{2}θ}$$.

If  $$ {cosAcotA \over( 1 - sinA ) }=x $$ then the value of x is : 

What is the value of $${tanθ−secθ+1\over tanθ+secθ-1}$$

If tanθ=1/5 then the value of Cosec²θ=?