00:01
We want to show this function is a solution of this differential equation.
00:06
So let's differentiate y.
00:08
You have y prime.
00:10
Two -fifth can be kept outside.
00:13
E to power minus 4x, when we differentiate, we get e to power minus 4x.
00:18
Differences the minus 4x.
00:19
We get minus 4.
00:21
Plus, e to power of x when we differentiate is just e to power x.
00:27
Okay, so we just tidy up a little bit.
00:37
Differencing one more time, we have, again, e to power minus 4x.
00:45
When we differentiate, we get minus 4, e to power minus 4 x.
00:51
And this, sorry, i missed out 2 5th.
00:54
And we have 2 plus 2 5th, e to power x...