Answer:
False.
Explanation:
The reflecting graph across y-axis
Rules of reflection :
Along across y-axis if we have a point

Along across x-axis if we have a point

here, we have y= cos x
So, along x-axis it will become -y=cosx implies y= -cos x
And along y-axis it will become y=cos(-x)=cos x
Hence, both of them are not equal
Therefore, false.