In two or more complete sentences describe why the range of y = cos (x) is - 1 ≤ y ≤ 1

The domain would be the x variable, which is undefined so can be any real number.

The magnitude of the term is the absolute value of the coefficient. Since the equation does not contain a coefficient, the magnitude becomes 1.

The lower bound of the range is the negative magnitude which would be - 1 and the upper bound is the magnitude, which is 1.

So the range is equal to - 1 ≤ y ≤ 1