Answer:
dA/dt = k1(M-A) - k2(A)
Step-by-step explanation:
If M denote the total amount of the subject and A is the amount memorized, the amount that is left to be memorized is (M-A)
Then, we can write the sentence "the rate at which a subject is memorized is assumed to be proportional to the amount that is left to be memorized" as:
Rate Memorized = k1(M-A)
Where k1 is the constant of proportionality for the rate at which material is memorized.
At the same way, we can write the sentence: "the rate at which material is forgotten is proportional to the amount memorized" as:
Rate forgotten = k2(A)
Where k2 is the constant of proportionality for the rate at which material is forgotten.
Finally, the differential equation for the amount A(t) is equal to:
dA/dt = Rate Memorized - Rate Forgotten
dA/dt = k1(M-A) - k2(A)
The key calculation in this problem is figuring out <em>how many times 80 goes into 1,000,000</em>. I'll build up in steps here.
80 x 5 = 400. This gives us a building block on our way to 1,000,000. From here, we can go further and say that 400 x 5 = 2,000; that 2,000 x 5 = 10,000; and finally that 10,000 x 100 = 1,000,000. Altogether, starting from 80, that's
80 x 5 x 5 x 5 x 100 = 80 x 25 x 500 = <em>80 x 12,500</em>
So, since 80 goes into one million 12,500 times, it takes 12,500 minutes for the animal's heart to beat that 1,000,000 times.
Remember you can do anything to an equaiton as long asyou do it to both sides
4v+18≥6v+10
minus 4v both sides
4v-4v+18≥6v-4v+10
0+18≥2v+10
18≥2v+10
minus 10 both sides
18-10≥2v+10-10
8≥2v+0
8≥2v
divide both sides by 2
8/2=(2v)/2
4≥(2/2)v
4≥1v
4≥v
v≤4
Answer:

Step-by-step explanation:

Answer:
true
Step-by-step explanation:
6(6(13x-2)
36(13x-2)
468x-72
please mark brainliest :D