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I Will give an expert or whoever knows how to do this 100 points. Can you help me Please!!!!! Pls don't take my points without doing the assignment right.Thank you !!!

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I Will give an expert or whoever knows how to do this 100 points. Can you help me-example-1
I Will give an expert or whoever knows how to do this 100 points. Can you help me-example-1
I Will give an expert or whoever knows how to do this 100 points. Can you help me-example-2
I Will give an expert or whoever knows how to do this 100 points. Can you help me-example-3

1 Answer

3 votes

I will do the first example, by explaining how to graph it. Then you can do the second example.


f(x) = x^3-10x^2+28x-24

We start by determining the the x-intercepts, by letting y = 0:


x^3-10x^2+28x-24=0,\\\left(x-2\right)^2\left(x-6\right)=0,\\x=2,\:x=6

The x-intercepts of the graph are (2, 0) and (6, 0) respectively. Now we determine the y-intercepts by letting x = 0:


f\left(x\right)=\left(0\right)^3-10\left(0\right)^2+28\left(0\right)-24 = - 24

So the y-intercept is (0, -24). But remember we need one more point, as there has to be a transition between the x-intercepts. This is the minimum of the graph. To determine this, we take the derivative of the function, and then equate it to 0 to find the "critical points." :


(d)/(dx)\left(x^3-10x^2+28x-24\right)\\\\ =>(d)/(dx)\left(x^3\right)-(d)/(dx)\left(10x^2\right)+(d)/(dx)\left(28x\right)-(d)/(dx)\left(24\right)\\\\=> 3x^2-20x+28-0\\=> 3x^2-20x+28

Now we equate this to 0, and apply the quadratic equation. In this case we can actually factor it :


3x^2-20x+28=0,\\\left(x-2\right)\left(3x-14\right)=0,\\\\x=2,\:x=(14)/(3)

x = 2 is our maximum, or our x-intercept (2, 0). Therefore we have to take 14/3 as our minimum, and determine the y-value:


f\left(x\right)=\left((14)/(3)\right)^3-10\left((14)/(3)\right)^2+28\left((14)/(3)\right)-24\\\\= -(256)/(27)

Minimum: (14/3, -256/27)

Graph is in the attachment below -

I Will give an expert or whoever knows how to do this 100 points. Can you help me-example-1
User Mellifluous
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