" (ii) "tan6^(@)tan42^(@)tan66^(@)tan78^(@)=1

Prove that: tan6^(0)tan42^(0)tan66^(@)tan78^(@)=1

The value of tan6^(@)tan42^(@)tan66^(@)tan78^(@) is (a) 1 (b) (1)/(2)(c)(1)/(4)(d)(1)/(8)

The value of tan6^(@)tan42^(@)tan66^(@)tan78^(@) is

The value of tan 6^(@) tan 42^(@) tan 66^(@) tan 78^(@) is

Prove that tan A. (tan 60^(@) +A). Tan (60^(@)-A)=tan 3A and hence find the value of tan 6^(@) tan 42^(@) tan 66^(@) tan 78^(@) .

tan 6 ^(@) tan 42 ^(@) tan 66 ^(@) tan 78^(@) =1