Here we want to solve differential equations, we will see that the general solution is:
We want to solve the differential equation:
From this is pretty clear that y is an exponential function, with an exponent of -1*t.
We can write it generally as:
Then if we set B = 100 we get:
So we just found the general form of the function.
Now we have two cases:
A) y(0) = 35
In this case, the function is:
B) y(0) = 125
In this case, the function is:
Now we want to see which one of the two can represent how a person learns. Just look at the graph below:
The green line is the one for y(0) = 35, and the blue one is for y(0) = 125.
Notice that for small values of t, the blue function is really large, thus it can't really model how a person learns (is larger for smaller values of t than for larger values).
So y(0) = 35 represents better how a <em>person can learn</em> (but not exactly, because you can see that it eventually becomes almost constant, which is something that really does not happen) so the correct option is <u>D: none of the above.</u>
If you want to learn more, you can read:
