How to find the values of A and C?

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1 Answer
Mar 6, 2018

#A=1/2#

#epsilon=-pi/3#

Explanation:

If we express a sine function in the following form:

#y=asin(bx+c)+d#

We have:

#bbacolor(white)(888.88)# is the amplitude.

#bb((2pi)/b)color(white)(8.88)# is the period

#bb((-c)/b)color(white)(.8.8)# is the phase shift.

#color(white)(8)bbdcolor(white)(88.8.8)# is the vertical shift.

So:

Amplitude will be the highest or lowest point on the graph. This can be seen to be #1/2#. The amplitude is given as an absolute value, so:

#|-1/2|=1/2#

If we look at:

#y=sinx#, we note that at #x=0# , #sinx=0#

From the graph we can see that the graph of #y=sinx# has been shifted to the right by #pi/3# units, This is the phase shift. From the above we have:

Phase shift is:

#(-c/b)#

#b=1#

#c=epsilon#

So:

#(-epsilon)/1=pi/3#

#epsilon=-pi/3#

The graph confirms this.

enter image source here