Answer:
288 trust me it is 100% right I tried it as an answer an got it right.
Step-by-step explanation:
Answer:
U=1-5(x-2)^2
Step-by-step explanation:
The equation of the parabola with vertex (h,k) is y=a(−h+x)2+k
Thus, the equation of the parabola is y=a(x−2)2+1
To find a, use the fact that the parabola passes through the point (3,−4): −4=a+1
Solving this equation, we get that a=−5
Thus, the equation of the parabola is y=1−5(x−2)^2
Y=2x
y is the amount of money made from the sold books
x is the number of books that are sold (it is x because you don't know how many will be sold, so you have to account for all possibilities)
2x is because every book is sold for 2 dollars, so that mean x is multiplied by 2 to get y
The first equation is linear:

Divide through by

to get

and notice that the left hand side can be consolidated as a derivative of a product. After doing so, you can integrate both sides and solve for

.
![\dfrac{\mathrm d}{\mathrm dx}\left[\dfrac1xy\right]=\sin x](https://tex.z-dn.net/?f=%5Cdfrac%7B%5Cmathrm%20d%7D%7B%5Cmathrm%20dx%7D%5Cleft%5B%5Cdfrac1xy%5Cright%5D%3D%5Csin%20x)


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The second equation is also linear:

Multiply both sides by

to get

and recall that

, so we can write



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Yet another linear ODE:

Divide through by

, giving


![\dfrac{\mathrm d}{\mathrm dx}[\sec x\,y]=\sec^2x](https://tex.z-dn.net/?f=%5Cdfrac%7B%5Cmathrm%20d%7D%7B%5Cmathrm%20dx%7D%5B%5Csec%20x%5C%2Cy%5D%3D%5Csec%5E2x)



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In case the steps where we multiply or divide through by a certain factor weren't clear enough, those steps follow from the procedure for finding an integrating factor. We start with the linear equation

then rewrite it as

The integrating factor is a function

such that

which requires that

This is a separable ODE, so solving for

we have



and so on.