Determine the amplitude

Question

Determine the amplitude of the following function:

y=3/5cos⁡(−7x)

Answer 1

amplitude = 3/5 = .6

Unless you really did mean

3/(5cos(-7x)) then amplitude is infinite, the interval (.6, infinity)

Answer 2

The amplitude of y = Acos(Bx) or y = Asin(Bx) is l A l.

So, the amplitude of y = (3/5)cos(-7x) is 3/5.