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24 votes
24 votes
5. Please verify correct

5. Please verify correct-example-1
User Bo Jeanes
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2 Answers

24 votes
24 votes

Answer: The function has a maximum value

The function's maximum value is 1

The function's maximum value occurs at x=-3

Explanation:

Given equation:
g(x) = -3x^ - 18x - 26

We shall use the differentiation method to find the answer.

Differentiating the equation, we get
g'(x) = - 6x - 18

equating g'(x) = 0,


-6x - 18 = 0\\-6x = 18 \\x = -3

Hence the minimum/ maximum value of the function lies in x = -3

on equating x>-3, g'(x) is negative

on equating x<-3, g'(x) is positive

this proves that first, the function was increasing and after x = -3, the function started to decrease hence at x=-3, the function g(x) was at its maximum value

The function's maximum value at x=-3 is


g(x) = -3x^2 - 18x - 26\\g(-3) = -3(-3)^2 - 18(-3) - 26\\g(-3) = -3(9) +54 -26\\g(-3) = 54 - 27 -26\\g(-3) = 1































User Roger Dahl
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2.8k points
19 votes
19 votes

Our function is a parabola, therefore, it has only one critical point which is its vertex. Since the coefficient of the squared term is negative, the vertex is the maximum point.The critical points of a function are given by the zeros of the first derivative. The first derivative of our function is:


f^(\prime)(x)=-6x-18

The solutions for the following equation are the critical points of the original function:


-6x-18=0\implies x=-3

The maximum point happens at x = - 3.

To find the corresponding value, we just have to evaluate x = - 3 into our function:


f(-3)=-3(-3)^2-18(-3)-26=1

The maximum value of the function is 1, and it occurs at x = - 3.