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love history [14]

3 years ago

6

The random variable X is normally distributed. P(2045).

1 answer:

bekas [8.4K]3 years ago

4 0

What the answer option

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I need help very fast please!

postnew [5]

I’m not sure maybe D

7 0

3 years ago

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When written in scientific notation, the number 4,500 will have a Choose... 2 4 3 as the exponent on the power of ten

nexus9112 [7]

The exponent would be 3.
4.5 x 10^3

6 0

3 years ago

Consider the differential equation:

Wewaii [24]

(a) Take the Laplace transform of both sides:

$2y''(t)+ty'(t)-2y(t)=14$

$\implies 2(s^2Y(s)-sy(0)-y'(0))-(Y(s)+sY'(s))-2Y(s)=\dfrac{14}s$

where the transform of $ty'(t)$ comes from

$L[ty'(t)]=-(L[y'(t)])'=-(sY(s)-y(0))'=-Y(s)-sY'(s)$

This yields the linear ODE,

$-sY'(s)+(2s^2-3)Y(s)=\dfrac{14}s$

Divides both sides by $-s$ :

$Y'(s)+\dfrac{3-2s^2}sY(s)=-\dfrac{14}{s^2}$

Find the integrating factor:

$\displaystyle\int\frac{3-2s^2}s\,\mathrm ds=3\ln|s|-s^2+C$

Multiply both sides of the ODE by $e^{3\ln|s|-s^2}=s^3e^{-s^2}$ :

$s^3e^{-s^2}Y'(s)+(3s^2-2s^4)e^{-s^2}Y(s)=-14se^{-s^2}$

The left side condenses into the derivative of a product:

$\left(s^3e^{-s^2}Y(s)\right)'=-14se^{-s^2}$

Integrate both sides and solve for $Y(s)$ :

$s^3e^{-s^2}Y(s)=7e^{-s^2}+C$

$Y(s)=\dfrac{7+Ce^{s^2}}{s^3}$

(b) Taking the inverse transform of both sides gives

$y(t)=\dfrac{7t^2}2+C\,L^{-1}\left[\dfrac{e^{s^2}}{s^3}\right]$

I don't know whether the remaining inverse transform can be resolved, but using the principle of superposition, we know that $\frac{7t^2}2$ is one solution to the original ODE.

$y(t)=\dfrac{7t^2}2\implies y'(t)=7t\implies y''(t)=7$

Substitute these into the ODE to see everything checks out:

$2\cdot7+t\cdot7t-2\cdot\dfrac{7t^2}2=14$

5 0

3 years ago

Solve<br> 7+x/3 = 2x-5<br> Give all working out

Ipatiy [6.2K]

X = 36/5
Or x = 7.2

21 + x = 6x - 15
21 = 6x - 15 - x
21 = 5x - 15
21 + 15 = 5x
36 = 5x
36/5 = x

7 0

3 years ago

Read 2 more answers

Identify the vertical asymptotes of f(x)=10/x^2-1

Brums [2.3K]

Answer:

-1 and 1

Step-by-step explanation:

5 0

3 years ago