Question

a sum of trigo........

Answer 1

Hi there!!

Refer to the attachment..

For solution we use two identities,
• 1/sin²x = cosec²x
• cosec²x- cot²x = 1

Hope it helps!!

Answer 2

Answer:

Step-by-step explanation:

$cot^{2}$θ - 1/$sin^{2}$θ

=> $cos^{2}$θ/ $sin^{2}$θ - 1/$sin^{2}$θ

=> $cos^{2}$θ - 1 / $sin^{2}$θ

=> -$sin^{2}$θ /$sin^{2}$ θ = -1