Question

What is the equation for this trig function?

(Open ended question)
Which trig function is the best representation for this graph?
A. sin (x)
B. - sin (x)
C. - cos (x)
D. cos (x)
Assuming that the scale for the y-axis is one box represents it be unit what could be the amplitude of this function?
A. 1
B. -1
C. 3
D. -3

Answer 1

A. y = cos x

Explanation:

The function that we see graphed has the point (0,1), this means whichever trig function f(x) it represents f(0) = 1.

Now, only the cosine function has the property that cos(0) = 1, thus choice A is the correct answer.

Explanation: