Question

show that tan48 tan16 tan42 tan74 =1

Answer 1

=tan48 tan16 cot48 cot 16
=tan A cotA =1
hence proved

Answer 2

Hello dear friend !

Here is your answer :-

tan48 tan16 tan42 tan74
= tan48 tan42 tan16 tan74
= tan48 cot48 tan16 cot16
= 1×1
=1

Hence proved.