00:01
Hello everyone, in this problem we are given with a non -homogeneous differential equation 4x2y' ' plus 9xy ' plus y to be equal to 20x plus 1.
00:17
So, for this non -homogeneous differential equation, now taking the homogeneous differential equation, this two equal to zero and it can be written as with the complementary function can be written as a into x inverse plus bx in power minus 1 by 4 and we are given with the value of yp that is the particular solution as 1 plus 2x where here a and b are constants.
00:50
Now by superposition principle, the solution of this general equation can be written as which is y to be equal to yc plus yp.
01:05
So, y will be a into x inverse plus b into x power minus 1 by 4 plus 1 plus 2x.
01:19
So, this is the required y.
01:22
Now we are we need to find the solution satisfying the initial conditions y of 1 equal to 4 and y ' of 1 which is equal to 9 as y of 1 equal to 4.
01:41
So, we have substituting the value of x as 1 in the obtained y equation.
01:47
So, we get a plus b plus 1 plus 2 which is equal to 4.
01:53
From this we get a plus b to be equal to 1.
01:56
Let us take this to be equation number 1.
02:00
So, this is nothing but y of x.
02:01
Also y ' of 1 to be equal to 9.
02:06
So, now we differentiate this y of x equation.
02:11
So, we get y ' of x to be equal to minus a into x power minus 2 minus 1 by 4 into b into x power minus 5 by 4 plus 2.
02:24
Now substituting this value of y ' of 1 equal to 9...