A-Level Maths: E5-01 [Trigonometric Identities: Proving tanθ = sinθ / cosθ]

[the_magicsmile]

your my hero thanks you i will finally get my A* in further maths

[stevebower]

I love Ramblin man fest too man! Keep up the good work and hopefully il see you at one next year

[PogbaMUFC]

could i be asked to prove this in the exam?

[evelynharris]

My friend came across this question and neither of us know how to solve part iii of the question.
I know it looks easy, and it only 4 marks.

"The acute angle x radians is such that tan x = k, where k is a positive constant. Express, in terms of k
i) tan(pi - x) [1]
ii) tan(1/2 pi - x) [1]
iii) sin(x) [2]"

For part ii I used tan(1/2 pi - x) = cot(x) which I then simplified to 1/tan(x) which then give me 1/k?
So for part iii use the identity tan(x) = sin(x)/cos(x)?