Answer:
Step-by-step explanation:
Answer:
m
Step-by-step explanation:
Let
Bas length of box=b
Height of box=h
Material used in constructing of box=36 square m
We have to find the height h and base length b of the box to maximize the volume of box.
Surface area of box=![2b^2+4bh](https://tex.z-dn.net/?f=2b%5E2%2B4bh)
![2b^2+4bh=36](https://tex.z-dn.net/?f=2b%5E2%2B4bh%3D36)
![b^2+2bh=18](https://tex.z-dn.net/?f=b%5E2%2B2bh%3D18)
![2bh=18-b^2](https://tex.z-dn.net/?f=2bh%3D18-b%5E2)
![h=\frac{18-b^2}{2b}](https://tex.z-dn.net/?f=h%3D%5Cfrac%7B18-b%5E2%7D%7B2b%7D)
Volume of box, V=![b^2h](https://tex.z-dn.net/?f=b%5E2h)
Substitute the values
![V=b^2\times \frac{18-b^2}{2b}](https://tex.z-dn.net/?f=V%3Db%5E2%5Ctimes%20%5Cfrac%7B18-b%5E2%7D%7B2b%7D)
![V=\frac{1}{2}(18b-b^3)](https://tex.z-dn.net/?f=V%3D%5Cfrac%7B1%7D%7B2%7D%2818b-b%5E3%29)
Differentiate w. r.t b
![\frac{dV}{db}=\frac{1}{2}(18-3b^2)](https://tex.z-dn.net/?f=%5Cfrac%7BdV%7D%7Bdb%7D%3D%5Cfrac%7B1%7D%7B2%7D%2818-3b%5E2%29)
![\frac{dV}{db}=0](https://tex.z-dn.net/?f=%5Cfrac%7BdV%7D%7Bdb%7D%3D0)
![\frac{1}{2}(18-3b^2)=0](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%2818-3b%5E2%29%3D0)
![\implies 18-3b^2=0](https://tex.z-dn.net/?f=%5Cimplies%2018-3b%5E2%3D0)
![\implies 3b^2=18](https://tex.z-dn.net/?f=%5Cimplies%203b%5E2%3D18)
![b^2=6](https://tex.z-dn.net/?f=b%5E2%3D6)
![b=\pm \sqrt{6}](https://tex.z-dn.net/?f=b%3D%5Cpm%20%5Csqrt%7B6%7D)
The negative value of b is not possible because length cannot be negative.
Again differentiate w.r.t b
![\frac{d^2V}{db^2}=-3b](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5E2V%7D%7Bdb%5E2%7D%3D-3b)
At
![\frac{d^2V}{db^2}=-3\sqrt{6}](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5E2V%7D%7Bdb%5E2%7D%3D-3%5Csqrt%7B6%7D%3C0)
Hence, the volume of box is maximum at
.
![h=\frac{18-(\sqrt{6})^2}{2\sqrt{6}}](https://tex.z-dn.net/?f=h%3D%5Cfrac%7B18-%28%5Csqrt%7B6%7D%29%5E2%7D%7B2%5Csqrt%7B6%7D%7D)
![h=\frac{18-6}{2\sqrt{6}}](https://tex.z-dn.net/?f=h%3D%5Cfrac%7B18-6%7D%7B2%5Csqrt%7B6%7D%7D)
![h=\frac{12}{2\sqrt{6}}](https://tex.z-dn.net/?f=h%3D%5Cfrac%7B12%7D%7B2%5Csqrt%7B6%7D%7D)
![h=\sqrt{6}](https://tex.z-dn.net/?f=h%3D%5Csqrt%7B6%7D)
m
3/4 is greater than 2/3 is the right one. Because 1/2 is more than 1/3. -1/4 is not less than -2/3, and -1 is not greater than 3/4s. I hope it helps
Answer: She will need 142 ft of curtain.
Step-by-step explanation:
Hi, first we have to convert the length of the curtain from inches to foot.
Since 1 inch = 1/12ft
For 24 inches:
24 inches x 1/12 = 2 ft
Since the company wants to make 71 curtains, we have to multiply the length of each curtain (2ft) by 71.
2ft x 71 = 142ft
She will need 142 ft of curtain.
Feel free to ask for more if needed or if you did not understand something.
The equation of a circle is:
(x-h)^2 + (y-k)^2 = r^2
where (h,k) is the location of the center and r is the radius. So we need to find h, k, and r. The center is given as (5,-4) so h = 5 and k = -4:
(x-5)^2 + (y-(-4))^2 = r^2
(x-5)^2 + (y+4)^2 = r^2
So we need to find r. Use the distance formula to find the distance between (5,-4) and (-3,2):
r = [(5-(-3))^2+((-4)-2)^2]^1/2
r = [8^2 + (-6)^2]^1/2
r = [64 + 36]^1/2
r = 100^1/2
r= 10
The final equation is:
(x-5)^2 + (y+4)^2 = 10^2