Which cube root function is always decreasing as x increases?

f(x) = RootIndex 3 StartRoot x minus 8 EndRoot
f(x) = RootIndex 3 StartRoot x EndRoot minus 5
f(x) = RootIndex 3 StartRoot negative (5 minux x) EndRoot
f(x) = Negative RootIndex 3 StartRoot x EndRoot + 5

Respuesta :

Answer:

Step-by-step explanation:

is an increasing function as when the value of x increases the value of y increases

And when the value of x decreases , the value of y also decreases.

Now if we have (x+a) or (x-a) instead of x, the function shall have a horizontal shift.

So it shall either move left or right but shall not flip.

So

and  

are increasing functions.

Only when x becomes -x, that the function shall flip & shall become a decreasing function.

But then it must be - (x-a) or -(x+a) inside.

So

is also increasing

Only

is a decreasing function.

Option D) is the right answer

The cube root is obtained by reversing the process of finding the cube of a

number, therefore, it can be negative.

  • The cube root function that is always decreasing is; [tex]\underline{f(x) = \sqrt[3]{5 - x} }[/tex]

Reasons:

The given options;

f(x) = ∛(x - 8)

f(x) = ∛(x) - 5

[tex]f(x) = \sqrt[3]{5 - x}[/tex]

f(x) = ∛(x) + 5

Required: The cube root that is always decreasing as x increases.

Solution:

∛(x³) = x

Therefore, as x increases, increases, and ∛(x³) = x increases

The analyzing the given options;

f(x) = ∛(x - 8)

In the above option, as x increases, (x - 8) increases, therefore, ∛(x - 8) increases

f(x) = ∛(x) - 5

In the above option, as x increases, ∛(x) increases, therefore, ∛(x) - 5 increases

  • [tex]\underline{f(x) = \sqrt[3]{5 - x} }[/tex]

In the above option, as x increases, (5 - x) decreases, therefore, ∛(5 - x) decreases.

Therefore, the above cube root function is always decreasing as x increases

f(x) = ∛(x) + 5

In the above option, as x increases, ∛(x) increases, therefore, ∛(x) + 5 increases.

The cube root function that is always decreasing as x increases is option;[tex]\underline{f(x) = \sqrt[3]{5 - x} }[/tex]

Learn more about decreasing functions here:

https://brainly.com/question/7128867

https://brainly.com/question/9214451