All categories

3 years ago

f(x)=3x^(4)-5x^(3)-5x^(2)+5x+2 The number 3 is an upper bound for the set of roots of this polynomial function True or False

Mathematics

1 answer:

Leona [35]3 years ago

7 0

Answer: TRUE

Step-by-step explanation: The number 3 is an upper bound because use 3 as a multiplyer of each bcoefficient of the polynomial and at each multiple,subtract the next coefficient from it. if all result after subtraction show positive, then the number used is an upper bound. This method is known as the synthetic division.

3 3 -5 -5 5 2

0 9 12 21 78

3 4 7 26 80

You might be interested in

Sarah bought a $320000 house. She pays 20% down and takes out a 30-year loan for the rest. How much is the loan amount going to

lana [24]

The first thing you do is mutitpy 320,000 by .20 so that you can find the amount of down payment. The down payment would be 64,000. So you subtract 64,000 from 320,000. This leaves a loan amount of 256,000 dollars. The answer is 256,000 dollars .

7 0

3 years ago

A metal cylinder can with an open top and closed bottom is to have volume 4 cubic feet. Approximate the dimensions that require

Aleksandr-060686 [28]

Answer:

$r\approx 1.084\ feet$

$h\approx 1.084\ feet$

$\displaystyle A=11.07\ ft^2$

Step-by-step explanation:

<u>Optimizing With Derivatives </u>

The procedure to optimize a function (find its maximum or minimum) consists in :

Produce a function which depends on only one variable
Compute the first derivative and set it equal to 0
Find the values for the variable, called critical points
Compute the second derivative
Evaluate the second derivative in the critical points. If it results positive, the critical point is a minimum, if it's negative, the critical point is a maximum

We know a cylinder has a volume of 4 $ft^3$ . The volume of a cylinder is given by

$\displaystyle V=\pi r^2h$

Equating it to 4

$\displaystyle \pi r^2h=4$

Let's solve for h

$\displaystyle h=\frac{4}{\pi r^2}$

A cylinder with an open-top has only one circle as the shape of the lid and has a lateral area computed as a rectangle of height h and base equal to the length of a circle. Thus, the total area of the material to make the cylinder is

$\displaystyle A=\pi r^2+2\pi rh$

Replacing the formula of h

$\displaystyle A=\pi r^2+2\pi r \left (\frac{4}{\pi r^2}\right )$

Simplifying

$\displaystyle A=\pi r^2+\frac{8}{r}$

We have the function of the area in terms of one variable. Now we compute the first derivative and equal it to zero

$\displaystyle A'=2\pi r-\frac{8}{r^2}=0$

Rearranging

$\displaystyle 2\pi r=\frac{8}{r^2}$

Solving for r

$\displaystyle r^3=\frac{4}{\pi }$

$\displaystyle r=\sqrt[3]{\frac{4}{\pi }}\approx 1.084\ feet$

Computing h

$\displaystyle h=\frac{4}{\pi \ r^2}\approx 1.084\ feet$

We can see the height and the radius are of the same size. We check if the critical point is a maximum or a minimum by computing the second derivative

$\displaystyle A''=2\pi+\frac{16}{r^3}$