143k views
4 votes

g(x) = 3 log(x + 7) - 8is this function increasing or decreasing?

1 Answer

7 votes

Given function : g(x)=3log(x+7) -8

A function is said to be increasing if the derivative of the function is greater than 0,

and it said to be decreasing tof the derivative of the function is less than 0,

Differentiate the given function with respect to x,

[tex]\begin{gathered} g(x)=3\log (x+7)-8 \\ \frac{dg(x)}{dx}=\frac{d(3\log (x+7)-8)}{dx} \\ g^{\prime}(x)=3\frac{d\log (x+7)}{dx}-\frac{d(8)}{dx} \\ g^{\prime}(x)=\frac{3}{x+7}-0 \\ g^{\prime}(x)=\frac{3}{x+7} \\ \text{ since if x}>7\text{ then the function will be negative, } \\ g^{\prime}(x)<0, \\ \text{thus function at }7Answer :

at x >7 , the function g(x) will be decreasing

at x <7 the function g(x) will be increasing.

User Svenson
by
8.8k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories