Toronto Math Forum
MAT2442019F => MAT244Test & Quizzes => Quiz4 => Topic started by: Mengyuan Wang on October 19, 2019, 04:46:15 PM

4y'' + 12y' + 9y = 0
let y = e^rt
y' = re^rt
y''= r^2e^rt
4r^2 + 12r +9r = 0
r = (2/3)
thus
y = c1e^((2/3))t + tc1e^((2/3))t