Question

Please please solve prove that

Answer 1

1 + tan^2(45-A) / 1 - tan^2(45-A)

let 45 - A = Φ

= ( sin^2Φ + cos^2Φ)/ cos^2Φ / (cos^2Φ - sin^2Φ)/cos^2Φ

= 1 / cos2Φ

= sec2(45-A)

= sec(90-2A)

= cosec2A

hoep it helped you