which of the following is true for f(x) = 5cos(x) +1?\nthe period of the function is 10π.\nthe function has…

which of the following is true for f(x) = 5cos(x) +1?\nthe period of the function is 10π.\nthe function has an amplitude of 2.5.\na zero of the function is (π/2,0).\nthe range of the function is the set of real numbers -4 ≤ y ≤ 6.
Answer
Explanation:
Step1: Recall the general form of a cosine - function
The general form of a cosine function is $y = A\cos(Bx - C)+D$, where $A$ is the amplitude, $B$ affects the period ($T=\frac{2\pi}{|B|}$), $C$ is the phase - shift, and $D$ is the vertical shift. For the function $f(x)=5\cos(x)+1$, we have $A = 5$, $B = 1$, $C = 0$, and $D = 1$.
Step2: Calculate the period
Using the formula $T=\frac{2\pi}{|B|}$, with $B = 1$, we get $T=\frac{2\pi}{|1|}=2\pi\neq10\pi$.
Step3: Calculate the amplitude
The amplitude $|A|$. Since $A = 5$, the amplitude is $|5| = 5\neq2.5$.
Step4: Check for a zero
Set $f(x)=0$, so $5\cos(x)+1 = 0$. Then $\cos(x)=-\frac{1}{5}$. When $x=\frac{\pi}{2}$, $\cos(\frac{\pi}{2}) = 0$, and $f(\frac{\pi}{2})=5\times0 + 1=1\neq0$. So $(\frac{\pi}{2},0)$ is not a zero of the function.
Step5: Find the range
The range of the cosine function $y = \cos(x)$ is $[- 1,1]$. For the function $y = 5\cos(x)+1$, when $\cos(x)=-1$, $y=5\times(-1)+1=-4$; when $\cos(x)=1$, $y=5\times1 + 1=6$. So the range of $y = 5\cos(x)+1$ is $-4\leq y\leq6$.
Answer:
The range of the function is the set of real numbers $-4\leq y\leq6$.