Answer-tan 20˚ x tan 23˚ x tan 67˚ x tan 70˚ = ?

We know that If tanA x tanB 1 then A B are complementary angles it means A B 90 Here 20 70 90 23 67 90 So tan 20 x tan 70 1 tan 23 x tan 67 1 Hence tan 20 x tan 23 x tan 67 x tan 70 1