Answer:
a) shown
b) h = [sqrt(17) - (5/2)t]²
c) t = 2sqrt(17)/5 seconds
Step-by-step explanation:
V = pi × r² × h
V = pi × 5² × h
V = 25pi × h
a) dV/dt = dV/dh × dh/dt
-5pi × sqrt(h) = 25pi × dh/dt
dh/dt = -sqrt(h)/5
b) 1/sqrt(h) .dh = -5. dt
2sqrt(h) = -5t + c
t = 0, h = 17
2sqrt(17) = 0 + c
c = 2sqrt(17)
2sqrt(h) = -5t + 2sqrt(17)
sqrt(h) = [2sqrt(17) - 5t] ÷ 2
sqrt(h) = sqrt(17) - (5/2)t
Square both sides
h = [sqrt(17) - (5/2)t]²
c) empty: h = 0
0 = [sqrt(17) - (5/2)t]²
sqrt(17) - (5/2)t = 0
(5/2)t = sqrt(17)
t = 2sqrt(17)/5
t = 1.64924225 seconds
sqrt: square root
Foil the binomials
First: n*n=n^2
Outer: n*-5=-5n
Inner: -3*n=-3n
Last: -3*-5=15
Put it together and simplify
n^2-5n-3n+15
n^2-8n+15
Final answer: A
Answer:
a) The present value is 688.64 $
b) The accumulated amount is 1532.60 $
Step-by-step explanation:
<u>a)</u><u> The preset value equation is given by this formula:</u>

where:
- T is the period in years (T = 10 years)
- r is the annual interest rate (r=0.08)
So we have:
Now we just need to solve this integral.

The present value is 688.64 $
<u>b)</u><u> The accumulated amount of money flow formula is:</u>

We have the same equation but whit a term that depends of τ, in our case it is 10.
So we have:
The accumulated amount is 1532.60 $
Have a nice day!
Keeping in mind that for a cost C(x) and profit P(x) and revenue R(x), the marginal cost, marginal profit and marginal revenue are respectively dC/dx, dP/dx and dR/dx, then
![\bf P(x)=0.03x^2-3x+3x^{0.8}-4400 \\\\\\ \stackrel{marginal~profit}{\cfrac{dP}{dx}}=0.06x-3+2.4x^{-0.2} \\\\\\ \cfrac{dP}{dx}=0.06x-3+2.4\cdot \cfrac{1}{x^{0.2}}\implies \cfrac{dP}{dx}=0.06x-3+2.4\cdot \cfrac{1}{x^{\frac{1}{5}}} \\\\\\ \cfrac{dP}{dx}=0.06x-3+\cfrac{2.4}{\sqrt[5]{x}}](https://tex.z-dn.net/?f=%5Cbf%20P%28x%29%3D0.03x%5E2-3x%2B3x%5E%7B0.8%7D-4400%0A%5C%5C%5C%5C%5C%5C%0A%5Cstackrel%7Bmarginal~profit%7D%7B%5Ccfrac%7BdP%7D%7Bdx%7D%7D%3D0.06x-3%2B2.4x%5E%7B-0.2%7D%0A%5C%5C%5C%5C%5C%5C%0A%5Ccfrac%7BdP%7D%7Bdx%7D%3D0.06x-3%2B2.4%5Ccdot%20%5Ccfrac%7B1%7D%7Bx%5E%7B0.2%7D%7D%5Cimplies%20%5Ccfrac%7BdP%7D%7Bdx%7D%3D0.06x-3%2B2.4%5Ccdot%20%5Ccfrac%7B1%7D%7Bx%5E%7B%5Cfrac%7B1%7D%7B5%7D%7D%7D%0A%5C%5C%5C%5C%5C%5C%0A%5Ccfrac%7BdP%7D%7Bdx%7D%3D0.06x-3%2B%5Ccfrac%7B2.4%7D%7B%5Csqrt%5B5%5D%7Bx%7D%7D)