cos(90-x)=sin(x) - Trigonometry

Sine and cosine are cofunctions of each other. The cosine of 90-x should be the same as the sine of x. This implies that graph of sine function is the same as shifting the graph of the cosine

Park School Mathematics

Notes on THE EQUATIONS IN TRIGONOMETRY

Domain & Range of Trigonometric Functions

List of trigonometric identities - Wikipedia

Sin(90-A), Sin(90+A), Cos(180-A), Cos(180+A), Sin(270-A), Sin(270+

sin(90°+θ) formula

Proof of sin(90-x) = cos x and cos(90-x) = sin x

cos(90-x)=sin(x) - Trigonometry

Trigonometry

Right Triangle Trigonometry

Which is correct, sin (x+90) =cosx or sin (90-x=cosx)? - Quora

4.10) Quiz 5: Answers – Trigonometry – Edexcel GCSE Maths Higher

sin(90-x)=cos(x) - Trigonometry

Small-Angle Approximation Brilliant Math & Science Wiki