A-Level Maths: H8-02 Differential Equations: A Worded Example 2

[elishamazvuma]

I just want to thank you ...your videos have been so helpful to me.

[aisha]

Hi, will the question always tell you whether something is directly/inversely proportional to something, or can it word it differently? for example, in a question I've seen it said the rate of increase of x is constant. in this case, what do you do?

[Reloaded]

at 6:48 shouldnt t = ( ln (1/20) / -1/10 ln (1/2) )

[file]

are we assuming here that A is a constant?

[Unlhd_tr]

itd be so great if you covered a level physics too!!

[manomaylr]

Hi, I have a Q which involves a differential equation - I got A = (20t/(1+19t))^2
I'm now asked to show that A cannot exceed 400/361
The Solution Bank says that as t tends to infinity, then A tends to 20/19
How does "tending to infinity" work as a concept?
Thanks!

[SimplySport]

How many marks would an exam question like this be worth I would think at least 7