How do you find the amplitude and period of f(x)=-4sin(7x+2)#?

1 Answer
Jul 4, 2015

Amplitude is #4#
Period is #2/7pi#

Explanation:

You must use the coefficients in front of #sin# and #x#:
1] Amplitude is #4# (the modulus of the coefficient #-4#), in this case your #sin# oscillates between #+4# and #-4#;
2] For the period you use the #7# in front of #x# in the argument of #sin# as:
#period=(2pi)/color(red)(7)# so your period will be #2/7pi=0.897~~0.9#.
Graphically you can see these values as:
graph{-4sin(7x+2) [-9.93, 10.07, -4.27, 5.73]}