Write the equation of a cosine function with the following properties

★ Analytical Trigonometry ★

Let it's general format be -

Having frequency as -

According to provided data -

amplitude : 3
Hence , a = 3


Hence b = 1

Phase Shift to the left of 2 : c = -2 [ left to the y-axis ]

Midline of y = 4

Hence d = 4

Now finally substituting every value obtained -

The equation of Cos function is -

I’m not sure how this works