Question

Find the amplitude, period, and phase shift of f(x)= -4sin(7x+2)

Not asking for the answer, I just don't know the formula for these.

Answer 1

The general form of the sine function is:

y = Asin(Bx + C) + D

where:
'A' is the amplitude of the function.
The period of the function is: T = 2pi/B
The phase shift of the function is: C/B

Answer 2

from here: http://www.teacherschoice.com.au/maths_library/functions/about_trigonometric_functions.htm

Answer 3

I'm getting medals for copying and pasting :P

Answer 4

lmao nice cx

Answer 5

Now all you do is compare your function to that form. And note that the amplitude will still be positive... negative amplitude doesn't make sense.

Answer 6

Sp even though the amplitude says -4 it is actually going to be 4?

Answer 7

Correct. Amplitude is just the height of the peaks/troughs. See picture http://www.teacherschoice.com.au/maths_library/functions/sine_function.gif

And you can't have a negative height, can you? :)

Answer 8

That's true c: