Answer:
Step-by-step explanation:
Let the other side of the rectangle be y. The perimeter of the rectangle is expressed as P = 2(x+y)
Given P = 30ft, on substituting P = 30 into the expression;
30 = 2(x+y)
x+y = 15
y = 15-x
Also since the area of the rectangle is xy;
A = xy
Substitute y = 15-x into the area;
A = x(15-x)
A = 15x-x²
The function that models its area A in terms of the length x of one of its sides is A = 15x-x²
The side of length x yields the greatest area when dA/dx = 0
dA/dx = 15-2x
15-2x = 0
-2x = -15
x = -15/-2
x = 7.5 ft
Hence the side length, x that yields the greatest area is 7.5ft.
Since y = 15-x
y = 15-7.5
y = 7.5
Area of the rectangle = 7.5*7.5
Area of the rectangle = 56.25ft²
I would say c hope this helps
Answer:
a) x=(t^2)/2+cos(t), b) x=2+3e^(-2t), c) x=(1/2)sin(2t)
Step-by-step explanation:
Let's solve by separating variables:

a) x’=t–sin(t), x(0)=1

Apply integral both sides:

where k is a constant due to integration. With x(0)=1, substitute:

Finally:

b) x’+2x=4; x(0)=5

Completing the integral:

Solving the operator:

Using algebra, it becomes explicit:

With x(0)=5, substitute:

Finally:

c) x’’+4x=0; x(0)=0; x’(0)=1
Let
be the solution for the equation, then:

Substituting these equations in <em>c)</em>

This becomes the solution <em>m=α±βi</em> where <em>α=0</em> and <em>β=2</em>
![x=e^{\alpha t}[Asin\beta t+Bcos\beta t]\\\\x=e^{0}[Asin((2)t)+Bcos((2)t)]\\\\x=Asin((2)t)+Bcos((2)t)](https://tex.z-dn.net/?f=x%3De%5E%7B%5Calpha%20t%7D%5BAsin%5Cbeta%20t%2BBcos%5Cbeta%20t%5D%5C%5C%5C%5Cx%3De%5E%7B0%7D%5BAsin%28%282%29t%29%2BBcos%28%282%29t%29%5D%5C%5C%5C%5Cx%3DAsin%28%282%29t%29%2BBcos%28%282%29t%29)
Where <em>A</em> and <em>B</em> are constants. With x(0)=0; x’(0)=1:

Finally:

Answer:
Step-by-step explanation:
We need to evaluate if thickness of a 10 gauge metal sheet is a requiered in the process that means 3.416 mm thick. So that should be our null hypothesis; μ₀ = 3.416 and based on sample data, we will formulate an alternative hypothesis taking into account the mean, and standard deviation obtained. We surely will have better information to take a decision