Which of the following functions are solutions of the differ
Which of the following functions are solutions of the differential equation y??6y?+9y=0 ?
Which of the following functions are solutions of the differential equation y\" - 6y\' + 9y = 0? A. y(x) = e^3x B. y(x) = 3x C. y(x) = e^-3x D. y(x) = xe^-3x E.y(x) = 0 F. y(x) = x^2 e^3x G. y(x) = xe^3xSolution
Given that
y\'\' - 6y\' + 9y = 0
Auxialary equation is ,
r2 - 6r + 9 = 0
r2 - 3r - 3r + 9 = 0
r(r - 3) - 3(r - 3) = 0
(r - 3)(r - 3) = 0
r - 3 = 0 , r - 3 = 0
r = 3 , r = 3
If the roots are real and equal then the solution is ,
y(x) = c1erx + c2xerx
y(x) = c1e3x + c2xe3x
Therefore ,
y(x) = e3x , y(x) = xe3x are solutions of given differential equation
......Options A , G are correct answers
