11 mark for review the function f is given by f(θ)=cosθ. if all of the other necessary conditions are met…

11 mark for review the function f is given by f(θ)=cosθ. if all of the other necessary conditions are met, which of the following could be modeled by f? a a scenario where the period is 1/2π and the initial value for θ = 0 is 0 b a scenario where the frequency is 1/2π and the initial value for θ = 0 is 0 c a scenario where the period is 1/2π and the initial value for θ = 0 is 1 d a scenario where the frequency is 1/2π and the initial value for θ = 0 is 1
Answer
Explanation:
Step1: Recall cosine - function properties
For the function $y = \cos\theta$, when $\theta=0$, $y = \cos(0)=1$. The general form of a cosine - function is $y = A\cos(B\theta - C)+D$. The period $T$ of the function $y=\cos\theta$ (where $B = 1$) is given by $T=\frac{2\pi}{|B|}=2\pi$, and the frequency $f=\frac{1}{T}=\frac{1}{2\pi}$.
Step2: Analyze each option
- Option A: The period of $y = \cos\theta$ is $2\pi$, not $\frac{1}{2\pi}$, and $\cos(0)=1\neq0$.
- Option B: The frequency of $y = \cos\theta$ is $\frac{1}{2\pi}$, but $\cos(0)=1\neq0$.
- Option C: The period of $y = \cos\theta$ is $2\pi$, not $\frac{1}{2\pi}$.
- Option D: The frequency of the function $y = \cos\theta$ is $f=\frac{1}{2\pi}$ (since $T = 2\pi$ and $f=\frac{1}{T}$), and when $\theta = 0$, $f(0)=\cos(0)=1$.
Answer:
D. A scenario where the frequency is $\frac{1}{2\pi}$ and the initial value for $\theta = 0$ is 1