Question

Select all the expressions that must be equivalent to cos A.

Answer 1

Given data:

The given right angle triangle.

The expression for cos(A) is,

`\begin{gathered} \cos (A)=\cos (x^(\circ)) \\ =\sin (90-x) \\ =\sin (y) \\ =\cos (90-y) \end{gathered}`

Thus, the given expression can be written as sin(90-x), sin(y), and cos(90-y), so options (B), (D) and (G) are correct.