To get the function y = <span>-2+5sin(pi/12(x-2)), the maximum value can be determined by differentiating the function and equating it to zero. The value of x will give the maximum value of the function.
dy/dx = 5 cos (pi/12 (x-2)) (pi/12)
dy/dx = 5 pi/12 cos(pi/12 (x-2))
Equate to zero</span>:
<span>5 pi/12 cos(pi/12 (x-2)) =0
pi/12 (x-2) = 3pi/2
x = 8
Substituting,
y= -2 + 5sin( pi/12 (8-2)
y = -1.86
</span>
144 is a square of 12
Hope this helps!
A graphing calculator can do a linear regression on these points very easily. The y-intercept is 107.
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If you want to do this by hand, you can use the 2-point form of the equation for a line, then evaluate for x=0.
.. y = (100 -102)/(35 -25)*(x -25) +102
.. y =-2/10*(0 -25) +102
.. y = 107