Cotangent quotient identity: cot θ = cos θ / sin θ
Cotangent is cosine over sine: cot θ = cos θ / sin θ. Together with tan θ = sin θ / cos θ it lets you rewrite any expression in sines and cosines alone - the standard opening move for an identity proof.
Related Quotient identities
Common questions
What is the cot θ = cos θ/sin θ identity?
Cotangent is cosine over sine: cot θ = cos θ / sin θ. Together with tan θ = sin θ / cos θ it lets you rewrite any expression in sines and cosines alone - the standard opening move for an identity proof.
Which identities are related to cot θ = cos θ/sin θ?
cot θ = cos θ/sin θ belongs to the Quotient group. The identities used alongside it most often are tan θ = sin θ/cos θ.
Practise it
Reading a formula is not the same as recalling it under time pressure. The workspace drills Quotient questions in the quiz, and the triangle solver shows a worked solution for any triangle you type in.
Or browse all 45 identities in the full reference, or read the trigonometry guides for the method behind them.