# need help fast

• Jun 25th 2008, 10:47 AM
Mr. red
need help fast
1. find three functions that reach a maximum value at (2,8) and a minimum value at (8,0) and meet the criteria shown below:
a) the function is in the form y=k+A cos(Bx+C) with A>0
b) the function is in the form y=K+A sin(Bx+C) with A<0
c) the function is in the form y=K+A sin(Bx+C) with A>0 which has different period than the function given in parts a) and b).

(Crying)
• Jun 25th 2008, 10:52 AM
mr fantastic
Quote:

Originally Posted by Mr. red
1. find three functions that reach a maximum value at (2,8) and a minimum value at (8,0) and meet the criteria shown below:
a) the function is in the form y=k+A cos(Bx+C) with A>0
b) the function is in the form y=K+A sin(Bx+C) with A<0
c) the function is in the form y=K+A sin(Bx+C) with A>0 which has different period than the function given in parts a) and b).

(Crying)

Median line is y = 4 (why?) => k = 4.
Amplitude = (8 - 0)/2 = 4.
Period/4 = 8 - 2 = 6 => period = 24. But period = 2pi/B => B = pi/12.

Try drawing some graphs using the above and then figure out for each case what C (horizontal translation) needs to be and whether A is positive or negative .....
• Jun 25th 2008, 10:55 AM
Mr. red
i need the three functions i don't to graph this problem
• Jun 25th 2008, 11:53 AM
mr fantastic
Quote:

Originally Posted by Mr. red
i need the three functions i don't to graph this problem

You try drawing some graphs to help you understand how to get the functions.

I have left you with two things to do and have suggested how to do them.

I also suggest you go back and revise this work so you have a better grasp of the concepts.

If you still have problems, show what you've tried and state where your trouble still is.