Izzy's heartbeat rate was measured on an EKG machine. After conversion, the function produced could be modeled by a sine function and the wave produced a maximum of 8, minimum of -2, and period of π. Which of the following functions could represent Izzy's EKG read-out?

Question

anonymous · Answer

a. f(x) = 8 sin πx - 2
b. f(x) = 5 sin πx + 3
c. f(x) = 5 sin 2x + 3
d. f(x) = 2 sin 2x + π

paounn · Answer

maximum of the A function is 8*1-2 = 6, so it can't be.
maximum of the D function is 2*1 +pi ~ 5, so it can't be either.
Both b and c are viable.
By definition of periodic function, if f(x) has period T, f(kx) has period T/k,
it means that the period of function b would be 2, and function c would be pi, which is the required answer.

anonymous · Answer

Okay, thank you for your help

anonymous · Answer

period is $\pi$ so go with $5\sin(2x)+3$

anonymous · Answer

the period of $\sin(2x)$ is $\frac{2\pi}{2}=\pi$