Answer:
The minimum value of y is -7
Step-by-step explanation:
Given:
We are given a cosine function.
We need to find minimum value of function.
Here y is depends on cosine function.
y is minimum when cosine is minimum because y is directly proportional to cosine function.
Minimum value of cos x is -1
Therefore, For minium value of y
Minimum value of y
Hence, The minimum value of y is -7