a cosine function that passes through the points (1/2,1) and (3/2,-3).

the equation is f(x)= 2cos(πx-π/2)-1
Maximum value: y=1
Minimum value: y=-3
Midline: y=-1

Identify phase shift

Phase shift: π/2

could you show how you found that using formulas

To find the phase shift, we need to use the general form of the cosine function:

f(x) = A * cos(Bx - C) + D

Given the equation f(x) = 2*cos(πx - π/2) - 1, we can see that:

A = 2
B = π
C = π/2
D = -1

The formula for phase shift is: phase shift = C / B

Plugging in the values, we get:

Phase shift = (π/2) / π
Phase shift = 1/2

Therefore, the phase shift is π/2 or 1/2 in decimal form.

Use phase shift and b to determine c. (phase shift = -c/b)

To determine the value of C using the phase shift, we can rearrange the formula:

Phase shift = -C / B

Given that the phase shift is 1/2 and B = π, we can plug in these values:

1/2 = -C / π

To solve for C, multiply both sides by π:

C = -π/2

Therefore, the value of C is -π/2.