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3 years ago

5

I will report u if you dont answer and take the points

1 answer:

IRINA_888 [86]3 years ago

4 0

Answer:

A

Step-by-step explanation:

A point estimate is the sample value which is used to estimate the population parameter

Sample characteristics for population mean is sample mean, which is 16.5

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Which set of ordered pairs is not a function?

USPshnik [31]

The correct answer is B

3 0

2 years ago

How to find 4x=14y and if it is parallel, perpendicular or neither to -2x+7y=14

RUDIKE [14]

4x = 14y
y = 4/14(x)
y = 2/7(x) slope = 2/7

<span>-2x+7y=14
7y = 2x + 14
y = 2/7(x) + 2 slope = 2/7

parallel lines, slope is the same
both lines have slopes equal 2/7

answer
</span><span>parallel</span>

7 0

3 years ago

Consider the initial value problem y′+5y=⎧⎩⎨⎪⎪0110 if 0≤t<3 if 3≤t<5 if 5≤t<[infinity],y(0)=4. y′+5y={0 if 0≤t<311 i

rosijanka [135]

It looks like the ODE is

$y'+5y=\begin{cases}0&\text{for }0\le t$

with the initial condition of $y(0)=4$ .

Rewrite the right side in terms of the unit step function,

$u(t-c)=\begin{cases}1&\text{for }t\ge c\\0&\text{for }t$

In this case, we have

$\begin{cases}0&\text{for }0\le t$

The Laplace transform of the step function is easy to compute:

$\displaystyle\int_0^\infty u(t-c)e^{-st}\,\mathrm dt=\int_c^\infty e^{-st}\,\mathrm dt=\frac{e^{-cs}}s$

So, taking the Laplace transform of both sides of the ODE, we get

$sY(s)-y(0)+5Y(s)=\dfrac{e^{-3s}-e^{-5s}}s$

Solve for $Y(s)$ :

$(s+5)Y(s)-4=\dfrac{e^{-3s}-e^{-5s}}s\implies Y(s)=\dfrac{e^{-3s}-e^{-5s}}{s(s+5)}+\dfrac4{s+5}$

We can split the first term into partial fractions:

$\dfrac1{s(s+5)}=\dfrac as+\dfrac b{s+5}\implies1=a(s+5)+bs$

If $s=0$ , then $1=5a\implies a=\frac15$ .

If $s=-5$ , then $1=-5b\implies b=-\frac15$ .

$\implies Y(s)=\dfrac{e^{-3s}-e^{-5s}}5\left(\frac1s-\frac1{s+5}\right)+\dfrac4{s+5}$

$\implies Y(s)=\dfrac15\left(\dfrac{e^{-3s}}s-\dfrac{e^{-3s}}{s+5}-\dfrac{e^{-5s}}s+\dfrac{e^{-5s}}{s+5}\right)+\dfrac4{s+5}$

Take the inverse transform of both sides, recalling that

$Y(s)=e^{-cs}F(s)\implies y(t)=u(t-c)f(t-c)$

where $F(s)$ is the Laplace transform of the function $f(t)$ . We have

$F(s)=\dfrac1s\implies f(t)=1$

$F(s)=\dfrac1{s+5}\implies f(t)=e^{-5t}$

We then end up with

$y(t)=\dfrac{u(t-3)(1-e^{-5t})-u(t-5)(1-e^{-5t})}5+5e^{-5t}$

3 0

3 years ago

Solve for x. a) 10 b) 12 c) 13 d) 11

Over [174]

Answer:

A : 10

Step-by-step explanation:

4 0

3 years ago

X-5=11-3x solve for x

defon

Answer:

4

Step-by-step explanation:

x-5=11-3x

+5 +5

x=16-3x

+3x +3x

4x=16

--- ----

4 4

//x= 4//

// have a great day //

6 0

2 years ago