Answer:
[tex]y=-\cos x[/tex]
Step-by-step explanation:
The given trigonometric graph is symmetric about the y-axis.
This means it is a cosine function.
The basic is symmetric about the y-axis and has a y-intercept of 1.
Its range is [tex]-1\le y\le1[/tex]
Since the given graph has y-intercept at -1 with the same range, it is the parent cosine function reflected in the x-axis.
Therefore its equation is [tex]y=-\cos x[/tex]
