All categories

3 years ago

Let p denote the population of the United States (in millions) in the year

Mathematics

1 answer:

Fofino [41]3 years ago

7 0

Answer:

dp/dt = 10⁻⁵p(2225 − 4.2381p)

Step-by-step explanation:

Since the function is

0 = ln p + 45.8177 − ln (2225 − 4.2381p) − 0.02225t

Differentiating the function implicitly with respect to time, we have

d0/dt = d[ln p + 45.8177 − ln (2225 − 4.2381p) − 0.02225t]/dt

d0/dt = d[ln p]/dt + d[45.8177]/dt − d[ln (2225 − 4.2381p)]/dt − d[0.02225t]/dt

0 = (1/p)dp/dt + 0 − (1/(2225 − 4.2381p)) × -4.2381 dp/dt − 0.02225

0 = (1/p)dp/dt + 4.2381 dp/dt/(2225 − 4.2381p) − 0.02225

-(1/p)dp/dt - 4.2381 dp/dt/(2225 − 4.2381p) = − 0.02225

(1/p)dp/dt + 4.2381 dp/dt/(2225 − 4.2381p) = 0.02225

Factorizing out dp/dt from the left hand side, we have

[(1/p) + 4.2381/(2225 − 4.2381p)]dp/dt = 0.02225

taking L.C.M of the left-hand-side and simplifying, we have

[((2225 − 4.2381p + 4.2381p)/p(2225 − 4.2381p)]dp/dt = 0.02225

[2225/p(2225 − 4.2381p)]dp/dt = 0.02225

dividing both sides by2225, we have

[1/p(2225 − 4.2381p)]dp/dt = 0.02225/2225

[1/p(2225 − 4.2381p)]dp/dt = 0.00001

[1/p(2225 − 4.2381p)]dp/dt = 10⁻⁵

multiplying both sides by p(2225 − 4.2381p), we have

p(2225 − 4.2381p)[1/p(2225 − 4.2381p)]dp/dt = 10⁻⁵p(2225 − 4.2381p)

So, dp/dt = 10⁻⁵p(2225 − 4.2381p)

You might be interested in

A radio station requires DJs to play 2 commercials for every 10 songs they play.What is the unit rate of songs to commercial?

Wittaler [7]

The DJs unit rate is 5 songs for every 1 commercial.

I found this by dividing both the commercials and the songs by their greatest common factor, or 2.

7 0

3 years ago

Read 2 more answers

The table shows the number of people per day who died from SARS in Singapore at two-week intervals beginning on March 1, 2003.

julia-pushkina [17]

Answer:

Step-by-step explanation:

check attachment for chart

(a) When a data set is given, the area can be calculated using either left Riemann sum (when we use left end points of each interval) or right Riemann sum (when we use right end points of each interval).

Here the intervals are:

|----------------Interval---------------||----left point--||--right point---|

March 1 - March 15 (t0 to t1) : y0 = 0.0079, y1 = 0.0638

March 15 - March 29 (t1 to t2) : y1 = 0.0638, y2 = 0.1944

March 29 - April 12 (t2 to t3) : y2 = 0.1944, y3 = 0.4435

April 12 - April 26 (t3 to t4) : y3 = 0.4435, y4 = 0.5620

April 26 - May 10 (t4 to t5) : y4 = 0.5620, y5 = 0.4630

May 10 - May 24 (t5 to t6) : y5 = 0.4630, y6 = 0.2897

Hence total no. of deaths using left end point:

$= y0.\bigtriangleup t + y1.\bigtriangleup t + y2.\bigtriangleup t + y3.\bigtriangleup t + y4.\bigtriangleup t + y5.\bigtriangleup t (\bigtriangleup t = 14 days)
\\\\=(y0 + y1 + y2+ y3 + y4 +y5).\bigtriangleup t
\\\\=(0.0079 + 0.0638 + 0.1944 + 0.4435 + 0.5620 + 0.4630) (14) = 24.2844 \approx 25 deaths (taking next integer value)
$

And total no. of deaths using right end point:

$= y1.\bigtriangleup t + y2.\bigtriangleup t + y3.\bigtriangleup t + y4.\bigtriangleup t + y5.\bigtriangleup t + y6.\bigtriangleup t (\bigtriangleup t = 14 days)
\\\\=(y1 + y2+ y3 + y4 + y5 + y6).\bigtriangleup t
\\\\=(0.0638 + 0.1944 + 0.4435 + 0.5620 + 0.4630 + 0.2897) (14) = 28.2296 \approx 29 deaths (taking next integer value)$

b) If we are given derivative of a function f(t) as a function of time, that is:

$\frac{\mathrm{d} }{\mathrm{d} t} (f(t)) = f'(t)
$

then the function can be evaluated by integrating both the sides. That is:

$f(t) = \int f'(t) dt
$

And by definition we know that integration of a curve gives area under the curve. Hence if we have data for SARS deaths per day (i.e. derivative of total deaths as a function of time) then, if this data is plotted on a curve, area under this curve will give us total no. of deaths during a time period.