Question

Please help me with a precalc assignment!

Given: A. sin(x) B. cos(x) C. cos(y) D. sin(y)

Use the drop-down menus in the derivation of the cosine sum identity:


sin(x + y)


= cos (StartFraction pi Over 2 EndFraction minus (x + y))


= Cosine ((StartFraction pi over 2 EndFraction minus x) minus y)


= Cosine (StartFraction pi Over 2 EndFraction minus x)

✔ C

+ Sine (StartFraction pi Over 2 EndFraction minus x)

A B C D

= sin(x)cos(y) + cos(x)sin(y)

Answer 1

Answer:

Trigonometric functions can be simply defined as the functions of an angle of a triangle.

The basic trigonometric functions are sine, cosine, tangent, cotangent, secant and cosecant.

sine sum identity:  

In sine sum identity , sin(x), cos(x), sin(y) and cos (y) is used.

Some identities shown below,

   Explanation:

so its c cos(x)