00:01
Okay, here i want to find da by dt.
00:03
So what i do is i take d by dt of both sides.
00:09
Differentiate both sides with respect to t.
00:17
Now, what i would get here, differentiate a5.
00:23
I can't find d by dt of a.
00:25
So i do it as da by dt times d by d a of a power 5.
00:34
Is the same thing i mean the das would cancel out left with d by d t of a 5 plus same idea here i can't find d by d t of b5 correctly so i do it as d b by d t times d by d b of b5 again you can see a cancel out most left d by d t of b5 now on the right, it's straightforward.
01:12
That is a number is constant so i get zero.
01:17
Now i have here then d -a by d -t and 5a to the fourth plus d -b by d -t and then 5b by d -t and then 5b to the fourth, differentiate b -5.
01:37
I want to find d -b, sorry, d -a by d -t when a is 2.
01:42
Well, first that, let's find what b would be.
01:46
So let's go back up to our equation then.
01:49
And we have a5 plus b5 is 275.
01:56
A is 2...