00:01
Hello students, in this problem we are going to find the general solution of y' ' plus 3y ' plus 2y is equal to 12e power x with the condition y of 0 is equal to 9 and y ' of 0 is equal to 4 is given.
00:27
First we need to find the axillary equation.
00:30
So axillary equation is m square plus 3m plus 2 equal to 0 solving m equal to minus 1 comma minus 2.
00:40
Here roots are different.
00:41
So complementary function is equal to a e power m1x plus b e power m2x.
00:50
Hence complementary function is equal to a e power minus x plus b e power minus 2x.
00:56
Next we have to find the particular solution and that is equal to 12 e power x divided by d square plus 3d plus 2.
01:10
We have to replace d by 1 since e power 1x is given.
01:17
So we have to replace d by 1.
01:19
The above terms becomes 12 e power x divided by 1 square plus 3 of 1 plus 2 that is equal to 12 e power x divided by 6 and this is equal to 2 e power x and the particular solution is 2 e power x and we know the general solution is y equal to complementary function plus particular integral and that is equal to a e power minus x plus b e power minus 2x plus 2 e power x.
01:57
Consider this as equation number 1...