00:01
Hi, in this question we are given that the force external is equal to 5 sine t plus 5 costi.
00:07
M is equal to 1, k2, b2, y of 0 is 1, y -dash of 0 is 2.
00:14
We have y double dash plus 2y dash plus 2y is equal to 5 sine t plus 5x t plus 5x t.
00:21
We will say that let y be equal to e raised to empty.
00:25
So derivative is equal to m e raised to empty, second derivative is equal to m, to m square e raise to mt.
00:34
Therefore we get m square e raise to mt plus 2 m e raise to mt plus 2 e raise to mt is equal to 0, which implies that m square plus 2m plus 2m plus 2 is equal to 0.
00:54
This implies m will be minus 1 plus i comma minus 1 minus i.
01:00
So, y of t is equal to e raise to minus t, a sine t plus b into cost t.
01:09
Name this as equation 1.
01:12
So the particular solution is yp is equal to c cos 3t plus d sine 3t.
01:19
First derivative will be minus 3c sine 3t plus 3d sign 3t.
01:25
Y p double dash means second derivative is minus 9c cause 3t minus 9c plus 3t minus 9.
01:30
D, sine 3t...