fina A B and C

• Mar 10th 2011, 12:46 PM
mwin002
fina A B and C
Y=Asin(BX+C)

the maximum value of y is 6 when x=0, y=6
the period of the graph is equal to PIE
A,B and C are positive and C is less than 2PIE

anybody???
• Mar 10th 2011, 12:50 PM
e^(i*pi)
The period is given by $\displaystyle P = \dfrac{2\pi}{B}$ - you are given that $\displaystyle P=\pi$

"Maximum Value" is a synonym of amplitude which is A in your equation

Now you know A you can find C by subbing in (0,6) for (x,y)
• Mar 10th 2011, 12:56 PM
HallsofIvy
Quote:

Originally Posted by mwin002
Y=Asin(BX+C)

the maximum value of y is 6 when x=0, y=6
the period of the graph is equal to PIE
A,B and C are positive and C is less than 2PIE

anybody???

First, it is "pi", not "pie".

The maximum value of y= A sin(Bx+ C) is A.

If for some x, Bx+ C= 0, the $\displaystyle Bx'+ C= 2\pi$ when (subtract the first equation from the second) $\displaystyle B(x'- x)= 2\pi$. Since we are told that the period is $\displaystyle \pi$, we can take $\displaystyle x'- x= \pi$ to get $\displaystyle B\pi= 2\pi$.

Finally, the maximum occurs at $\displaystyle \pi/2$. Since we are told that it happens when x= 0, we must have $\displaystyle A(0)+ B= B= \pi/2$.
• Mar 10th 2011, 03:41 PM
mwin002
i dont get....im a surveyor not a math guru...i need to work these out for my unit standards but god dam i cant get my head around...

thanks for tryinh to help