Given the points (1/2, 1) and (3/2, -3), we can use the cosine function equation:
y = a cos(bx) + c
Substitute the points into the equation:
1 = a cos(b(1/2)) + c
-3 = a cos(b(3/2)) + c
This gives us the two equations:
1 = a cos(b/2) + c
-3 = a cos(3b/2) + c
Solving for c in the first equation:
c = 1 - a cos(b/2)
Substitute c into the second equation and solve for a:
-3 = a cos(3b/2) + 1 - a cos(b/2)
-4 = a (cos(3b/2) - cos(b/2))
a = -4 / (cos(3b/2) - cos(b/2))
Now that we have the values of a and c, we can determine the value of b using the midpoint of the maximum and minimum values of the function:
Midpoint = (Maximum + Minimum) / 2
-1 = (1 + (-3)) / 2
Substitute into the original equation:
-1 = a cos(bx) + c
-1 = a cos(bx) + 1 - a cos(b/2)
-2 = a (cos(bx) - cos(b/2))
Solve for b:
-2 = a (cos(bx) - cos(b/2))
-2 = -4 / (cos(3b/2) - cos(b/2)) (cos(bx) - cos(b/2))
cos(bx) - cos(b/2) = 2 / (cos(3b/2) - cos(b/2))
This will give us the value of b for the cosine function that passes through the given points.
a cosine function that passes through the points (1/2,1) and (3/2,-3).
Maximum value: y=1
Minimum value: y=-3
Midline: y=-1
determine b
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