1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Andreas93 [3]
3 years ago
6

Someone help me please!!?? I don’t understand please

Mathematics
1 answer:
lisabon 2012 [21]3 years ago
5 0
Use PEMDAS so do (-3/2) first. and then rewrite it and keep doing pemdas
You might be interested in
What is the constant term of -3x^4-7x+2
san4es73 [151]

Answer:

The answer is 2. 2 is the only number that can't change. There is no x or ^.

4 0
3 years ago
3) James earned a total of $900 last week. He worked for 5 hours at his usual rate, then earned a bonus of $20 for each hour tha
agasfer [191]

Answer:

$160 hourly rate

Step-by-step explanation:

20 x 5 = 100

900 - 100 = 800

800 ÷ 5 = 160

To check: Multiply 160 by 5 and then add 100

3 0
2 years ago
Solve the following differential equation using using characteristic equation using Laplace Transform i. ii y" +y sin 2t, y(0) 2
kifflom [539]

Answer:

The solution of the differential equation is y(t)= - \frac{1}{3} Sin(2t)+2 Cos(t)+\frac{5}{3} Sin(t)

Step-by-step explanation:

The differential equation is given by: y" + y = Sin(2t)

<u>i) Using characteristic equation:</u>

The characteristic equation method assumes that y(t)=e^{rt}, where "r" is a constant.

We find the solution of the homogeneus differential equation:

y" + y = 0

y'=re^{rt}

y"=r^{2}e^{rt}

r^{2}e^{rt}+e^{rt}=0

(r^{2}+1)e^{rt}=0

As e^{rt} could never be zero, the term (r²+1) must be zero:

(r²+1)=0

r=±i

The solution of the homogeneus differential equation is:

y(t)_{h}=c_{1}e^{it}+c_{2}e^{-it}

Using Euler's formula:

y(t)_{h}=c_{1}[Sin(t)+iCos(t)]+c_{2}[Sin(t)-iCos(t)]

y(t)_{h}=(c_{1}+c_{2})Sin(t)+(c_{1}-c_{2})iCos(t)

y(t)_{h}=C_{1}Sin(t)+C_{2}Cos(t)

The particular solution of the differential equation is given by:

y(t)_{p}=ASin(2t)+BCos(2t)

y'(t)_{p}=2ACos(2t)-2BSin(2t)

y''(t)_{p}=-4ASin(2t)-4BCos(2t)

So we use these derivatives in the differential equation:

-4ASin(2t)-4BCos(2t)+ASin(2t)+BCos(2t)=Sin(2t)

-3ASin(2t)-3BCos(2t)=Sin(2t)

As there is not a term for Cos(2t), B is equal to 0.

So the value A=-1/3

The solution is the sum of the particular function and the homogeneous function:

y(t)= - \frac{1}{3} Sin(2t) + C_{1} Sin(t) + C_{2} Cos(t)

Using the initial conditions we can check that C1=5/3 and C2=2

<u>ii) Using Laplace Transform:</u>

To solve the differential equation we use the Laplace transformation in both members:

ℒ[y" + y]=ℒ[Sin(2t)]

ℒ[y"]+ℒ[y]=ℒ[Sin(2t)]  

By using the Table of Laplace Transform we get:

ℒ[y"]=s²·ℒ[y]-s·y(0)-y'(0)=s²·Y(s) -2s-1

ℒ[y]=Y(s)

ℒ[Sin(2t)]=\frac{2}{(s^{2}+4)}

We replace the previous data in the equation:

s²·Y(s) -2s-1+Y(s) =\frac{2}{(s^{2}+4)}

(s²+1)·Y(s)-2s-1=\frac{2}{(s^{2}+4)}

(s²+1)·Y(s)=\frac{2}{(s^{2}+4)}+2s+1=\frac{2+2s(s^{2}+4)+s^{2}+4}{(s^{2}+4)}

Y(s)=\frac{2+2s(s^{2}+4)+s^{2}+4}{(s^{2}+4)(s^{2}+1)}

Y(s)=\frac{2s^{3}+s^{2}+8s+6}{(s^{2}+4)(s^{2}+1)}

Using partial franction method:

\frac{2s^{3}+s^{2}+8s+6}{(s^{2}+4)(s^{2}+1)}=\frac{As+B}{s^{2}+4} +\frac{Cs+D}{s^{2}+1}

2s^{3}+s^{2}+8s+6=(As+B)(s²+1)+(Cs+D)(s²+4)

2s^{3}+s^{2}+8s+6=s³(A+C)+s²(B+D)+s(A+4C)+(B+4D)

We solve the equation system:

A+C=2

B+D=1

A+4C=8

B+4D=6

The solutions are:

A=0 ; B= -2/3 ; C=2 ; D=5/3

So,

Y(s)=\frac{-\frac{2}{3} }{s^{2}+4} +\frac{2s+\frac{5}{3} }{s^{2}+1}

Y(s)=-\frac{1}{3} \frac{2}{s^{2}+4} +2\frac{s }{s^{2}+1}+\frac{5}{3}\frac{1}{s^{2}+1}

By using the inverse of the Laplace transform:

ℒ⁻¹[Y(s)]=ℒ⁻¹[-\frac{1}{3} \frac{2}{s^{2}+4}]-ℒ⁻¹[2\frac{s }{s^{2}+1}]+ℒ⁻¹[\frac{5}{3}\frac{1}{s^{2}+1}]

y(t)= - \frac{1}{3} Sin(2t)+2 Cos(t)+\frac{5}{3} Sin(t)

3 0
3 years ago
2x-14=-3x+6&lt;br /&gt;<br>help with this equation???&lt;br /&gt;
Sphinxa [80]
2x-14=-3x+6
You need to combine like terms and get all the x's on one side and the numbers on the other
2x+3x-14=6
5x=6+14
5x=20
now divide to get x alone
x=4

Hope that helps
5 0
3 years ago
Read 2 more answers
Please help meee please explain it
iren2701 [21]

Answer:

C. .45

Step-by-step explanation:

Think of it like this: that is 45 hundredths and you are trying to find what 45% is and it is like 45/100 so .45 is your answer.

4 0
2 years ago
Read 2 more answers
Other questions:
  • T sanger's auto garage, three out of every five cars brought in for service need an oil change. of the cars that need an oil cha
    5·1 answer
  • If the height of a triangle is 12 and its area is 54, what is its base?
    14·1 answer
  • Here are some equationsfor you to solve. each problem takes two steps. First simplify the equation by combining like terms. Then
    14·1 answer
  • What is the value of the discriminant for the quadratic equation?<br> 6x^2 - 2x + 5 = 0
    9·1 answer
  • Kayleigh has 3 1/2 gallons of water. She wants to fill up 1/3 cups. How many cups can she fill and how much is left over?
    12·2 answers
  • Which of these inequalities are equivalent to r &gt; -11? Check all that apply.
    13·2 answers
  • What is the area of a 24-inch rug? Use area of a circle formula: A = πr²
    11·1 answer
  • 5 divided by 925 =?<br><br> please step by step
    9·1 answer
  • 3.6.PS-8 If the simple interest on $5,000 for 9 years is $2,700, then what is the interest rate? The rate is %. .​
    15·1 answer
  • Find the slope of the line passing through the points (-7 ,-7) and (-3,6)
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!