Solve the second order ODE, giving a general solution: x'' + 2x' - 3x = 2e^-t

First find an auxiliary equation, for the complimentary function:m^2 + 2m - 3 = 0, (m+3)(m-1)=0m=1 or m=-3So the complimentary function is: x= Ae^t + Be^-3tFor the particular integral (PI), let x = Ue^-tthen x' = -Ue^-tand x'' = Ue^-tBy substituting these in : U(e^-t) - 2U(e^-t) -3U(e^-t) = 2e^-tDividing by e^-t, -4U=2, U=-0.5So the PI is: x= 0.5e^-tAnd, finally, the general solution is: x= Ae^t +Be^-3t +0.5e^-t

IF
Answered by Isaac F. Further Mathematics tutor

2301 Views

See similar Further Mathematics A Level tutors

Related Further Mathematics A Level answers

All answers ▸

The plane Π contains the points (1, 2, 3), (0, 1, 2) and (2, 3, 0). What is the vector equation of the plane? and what is the cartesian equation of the plane?


Find the general solution of the second order differential equation y''(t)+y(t) = 5exp(2t)


A golf ball is hit from horizontal ground with speed 10 m/s at an angle of p degrees above the horizontal. The greatest height the golf ball reached above ground level is 1.22m. Model the golf ball as a particle and ignore air resistance. Find p.


Let E be an ellipse with equation (x/3)^2 + (y/4)^2 = 1. Find the equation of the tangent to E at the point P where x = √3 and y > 0, in the form ax + by = c, where a, b and c are rational.


We're here to help

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

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning