`tan75^@+tan15^@=….`

Prove that : tan15^@.tan25^@+tan25^@.tan50^@+tan50^@.tan15^@=1.

tan75^@-cot75^@=

tan 75^(@)+ tan 15^(@)= A)1B)2C)3D)4

Show that tan 15^@+ tan 75^@ = (sec^2 15^@)/sqrt(sec^2 15^@-1)

Find sin15^@ ,cos15^@ ,tan15^@ ,hence evaluate cot75^@ +tan75^@ .

The value of tan 10^@ tan 15^@ 75^@ tan 80^@ is___

Find the value of ((tan20^(@))/(cos e)c70^(@))^(2)+((cot20^(@))/(sec70^(@)))^(2)+2tan75^(@)tan45^(@)tan15^(@)

If tan 15^@=2-sqrt3 , then the value of tan15^@ cot 75^@+tan75^@ cot 15^@ is

(i) cos 15^@ (ii) cos75^@ (iii) tan15^@ (iv)tan75^@

Write the value of tan10^@tan15^@tan75^@tan80^@ .