Evaluate without using trigonometric tables :
`tan 20.tan 40^(@) tan 50^(@) tan 70^(@)`

(tan8 0^(@)-tan1 0^(@))/tan70^(@)

tan 20^(@) tan 40^(@) tan 80^(@) = tan 60^(@)

Without using trigonometric tables , prove that : (i) tan20^(@)tan40^(@) tan45^(@)tan50^(@)tan70^(@)=1 (ii) tan1^(@) tan2^(@)tan60^(@)tan88^(@)tan89^(@)=sqrt(3) (iii) cot5^(@)cot10^(@)cot30^(@)cot80^(@)cot85^(@)=sqrt(3) (iv) 4sin10^(@)sin20^(@)sin30^(@)sec70^(@)sec80^(@)=2

Evaluate without using trigonometric tables. 2(("tan" 35^(@))/("cot" 55^(@)))^(2)+(("cot" 55^(@))/("tan" 35^(@)))^(2)-3(("sec" 40^(@))/("cosec" 50^(@)))

Evaluate without using trigonometric tables : "cos"^(2) 26^(@)+"cos" 64^(@)"sin" 26^(@)+("tan" 36^(@))/("cot" 54^(@))

Evaluate : tan 40^(@)xxtan 50^(@)

Prove that : tan 70^(@) = tan 20^(@) + 2 tan 50^(@)

The value of tan20^(@)+2 tan50^(@)-tan70^(@), is

Prove that tan40^(@) + 2tan10^(@) = tan50^(@)

Evaluate tan20^(@)tan25^(@)tan65^(@)tan70^(@) .