Question

please answer this question answer please​

Answer 1

Answer:

it's not clear ok #$given tan2θ=2tan2ϕ+1 

⇒1+tan2θ=2(1+tan2ϕ)⟶(1)

now, cos2θ+sin2ϕ=1+tan2θ1−tan2θ+1−1+tan2ϕ1 

                                    =1+tan2θ1−tan2θ+1−1+tan2θ2,  using equation (1)

                                    =0

Hence, option 'B' is correct.

Answer 2

Answer:

4)Since the interior angle is 144 degree, each exterior angle is 180 - 144 = 36 degrees.

For any convex polygon (in particularly, for any regular polygon) the sum of exterior angles is 360 degrees.

Hence, the number of sides = the number of vertices = 360%2F36 = 10.

Answer. Your polygon is decagon with 10 sides (vertices).