Write and solve the differential equation that models the verbal statement. Using k for the constant of proportionality

The rate of change of N with respect to s is proportional to 626 − s.
dN/ds=
N=

To write and solve the differential equation that models the given verbal statement, we need to express the rate of change of N with respect to s and set it proportional to the expression "626 - s" using the constant of proportionality k.

So, the differential equation can be written as:

dN/ds = k(626 - s)

To solve this differential equation, we will use separation of variables technique:

Step 1: Move the differentials to one side and the terms involving N and s to the other side.

1/(626 - s) dN = k ds

Step 2: Integrate both sides of the equation.

∫ (1/(626 - s)) dN = ∫ k ds

This gives us:

ln|626 - s| + C1 = ks + C2

Where C1 and C2 are integration constants.

Step 3: Simplify the equation.

ln|626 - s| = ks + C

Where C = C2 - C1 is a new integration constant.

Step 4: Eliminate the natural logarithm by taking the exponential of both sides.

e^(ln|626 - s|) = e^(ks + C)

This simplifies to:

|626 - s| = e^C * e^(ks)

Step 5: Remove the absolute value by separating into two cases.

For (626 - s) > 0:

626 - s = A * e^(ks), where A = e^C

For (626 - s) < 0:

s - 626 = A * e^(ks), where A = -e^C

So we have two separate solutions:

Case 1: (626 - s) > 0

N = A * e^(ks) + C3

Case 2: (626 - s) < 0

N = -A * e^(ks) + C4

Where C3 and C4 are integration constants.

These are the solutions to the differential equation that models the given verbal statement, representing the rate of change of N with respect to s, proportional to 626 - s.