Question

for the function given, state the middle line: ƒ(t) = 3 cos(π t − 1).

Answer 1

Cos (πt - 1) oscilates periodically between -1 and +1.

3Cos (πt - 1) oscilates periodically between -3 and +3.

The x-axis is the middle line. The equation of the x-axis is y = 0.

So the, the middle line is y=0.