Trig Identities

Question

Which statement is equivalent to sinθ+cosθ-cotθ=secθ?

A.tanθ+1−cscθ=secθ

B.2−cscθ=sec^2(θ)

C.tanθ+1−cscθ=sec^2(θ)

D.sinθ+cosθ−tanθ=1/sinθcosθ

Answer 1

If you divide both sides of sinθ+cosθ-cotθ = secθ by cosθ:

sinθ/cosθ+1-1/sinθ = 1/cos²θ

Which is the same as:

tanθ + 1 - cscθ = sec²θ

Which is answer C