Find the general solution of the differential equation d^2y/dx^2 - 5*dy/dx + 4y = 2x

Solve complimentary function: Let y = emx then,
d2y/dx2 - 5dy/dx + 4y = 0
m2emx - 5memx + 4emx = 0 (substituting for y)
emx(m2 - 5m + 4) = 0
emx(m - 4)(m - 1) = 0
Therefore m=4 and m=1, so the c.f. is y = Ae4x + Bex where A,B are constants

Solve particular integral: Let y = ax + b and substitute into the differential equation
0 - 5a + 4(ax + b) = 2x
4ax + (4b - 5a) = 2x
Therefore 4a=2 and 4b-5a=0 so a=1/2, b =5/8

Hence the general solution is y = c.f + p.i =  Ae4x + Bex + 1/2 x + 5/8

PM
Answered by Peter M. Further Mathematics tutor

12273 Views

See similar Further Mathematics A Level tutors

Related Further Mathematics A Level answers

All answers ▸

Given that abc = -37 + 36i; b = -2 + 3i; c = 1 + 2i, what is a?


Let A, B and C be nxn matrices such that A=BC-CB. Show that the trace of A (denoted Tr(A)) is 0, where the trace of an nxn matrix is defined as the sum of the entries along the leading diagonal.


Find the eigenvalues and eigenvectors of the matrix M , where M{2,2} = (1/2 2/3 ; 1/2 1/3) Hence express M in the form PDP^-1 where D is a diagonal matrix.


Why is the argument of a+bi equal to arctan(b/a)?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences