00:01
Hi, in this question we have been given an equation that is y double dash plus 3y dash is equal to 0.
00:12
Consider the condition y of 0 is equal to a 0, y dash of 0 is equal to a 1.
00:18
Let y will be equal to summation n greater than equal to 0 a n x raised 2 n, y dash will be equal to summation n greater than equal to 0 a n x raised 2 n.
00:31
N greater than equal to 0 n plus 1 a n plus 1 x raised to n and y double dash will be equal to summation n greater than equal to 0 into n plus 1 into n plus 2 a n plus 2 a n plus 2 x raised to n therefore summation n greater than equal to 0 n plus 1 into n plus 2 a n plus 2 x raise to n plus 3 submission n greater than equal to 0 n plus 1 gain plus 1 x raised to n is equal to 0 so summation n greater than equal to 0 n plus 1 into n plus 2 a n plus 2 plus 3 into n plus 1n plus 1 into x raised 2 n is equal to 0 therefore n plus 1 into n plus 2 a n plus 2 plus 3 n plus 1 a n plus 1 is equal to 0 for n greater than equal to 0 or we'll say that n minus 1 n minus 1 a n plus 3 into n minus 1 a n minus 1 is equal to 0 which implies that a n will be equal to minus 3 by n, a n minus 1.
01:54
Now we can say that for n greater than equal to 2, notice that this implies a dependency for all the an beyond n is equal to 1 on a1, while a0 takes on whatever initial value y of 0 is given.
02:11
So it can be said that in particular, a2 is equal to minus 3 divided by 2, a1, a3 will be equal to minus 3 divided by 3a2 which is equal to 3 squared divided by 3 into 2a1 that is equal to 3 square divided by 3 factorial a 1.
02:44
So we will get a4 as minus 3 cube divided by 4 factorial a 1.
02:54
Therefore, an is equal to minus 3 raise to n minus 1 divided by n factorial into a1.
03:00
The two fundamental solutions, y1, y2, is such that y is equal to y1 plus y2 where y1 is equal to a, 2, y2 is equal to minus 3 a 1, summation n greater than equal to 1 minus 3 x raised 2 n divided by n factorial.
03:16
Recall e raise 2 x is equal to summation n greater than equal to 0 x raised to n divided by n factorial...