If cosec2 x - cosec x = 1, then cot6 x + 3cot10 x - 3cot8 x - cot12 x + 4 =?
Answer & explanation
Correct answer: option 2
cot6 x+ 3cot10 x - 3cot8 x - cot12 x + 4
⇒ (cot2 x - cot4 x)3 + 4
Now, cosec2 x - cosec x = 1 (cot2 x - cosec2 x)3 + 4
1 - cosec2 x = cosec x (-1)3 + 4
cot2 x = cosec x (Put in 1) = 3