Question

Use a graph to find the range of the function f(x) = 5/x^2
on the domain -5 < x < 5.

Answer 1

Answer:

Option A.

Step-by-step explanation:

The given function is  

$f(x)=\dfrac{5}{x^2}$

We need to find the range of the function f(x) on the domain $-5\leq x\leq 5$.

At x=-5,

$f(-5)=\dfrac{5}{(-5)^2}=\dfrac{5}{25}=\dfrac{1}{5}$

At x=5,

$f(5)=\dfrac{5}{(5)^2}=\dfrac{5}{25}=\dfrac{1}{5}$

As x approaches to 0, then the function approaches to positive infinity.

Draw the graph of given function as shown below.

In the graph x-axis represents the domain and y-axis represents the range.

From the graph it is clear that on the domain $-5\leq x\leq 5$ the value of function is greater than or equal to $\dfrac{1}{5}$.

So, range is $f(x)\geq \dfrac{1}{5}.$

Therefore, the correct option is A.