Author Topic: Quiz 4 TUT0202  (Read 710 times)

Mengyuan Wang

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Quiz 4 TUT0202
« 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