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Given f(x)=-(7)/(3)x^(3)+nx^(2)-3x+13, find a value for n so f(x) has an inflection point at x=-3

User Rachid O
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To find a value for n such that the function f(x) has an inflection point at x = -3, we need to examine the second derivative of the function.

The second derivative, denoted as f''(x), represents the rate of change of the first derivative of the function. An inflection point occurs when the concavity of the function changes, which is indicated by the second derivative changing sign.

Given f(x) = -(7/3)x^3 + nx^2 - 3x + 13, we will first find the second derivative, f''(x), and then substitute x = -3 into it to determine the value of n.

Let's begin by finding the first derivative of f(x):

f'(x) = d/dx [-(7/3)x^3 + nx^2 - 3x + 13]

= -7x^2 + 2nx - 3

Now, let's find the second derivative by differentiating f'(x):

f''(x) = d/dx [-7x^2 + 2nx - 3]

= -14x + 2n

Now, substitute x = -3 into f''(x) and set it equal to zero, as an inflection point occurs when the second derivative is zero:

-14(-3) + 2n = 0

Simplifying the equation:

42 + 2n = 0

2n = -42

n = -21

Therefore, for f(x) to have an inflection point at x = -3, the value of n should be -21.

User HeatfanJohn
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