Author Topic: TUT0101 QUIZ4  (Read 5101 times)

Yiheng Bian

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TUT0101 QUIZ4
« on: October 18, 2019, 08:41:21 PM »
$$
\text{The question is } 9y''+9y'-4y=0
$$
$$
9r^2+9r-4=0
$$
$$
\text{So r1}=\frac{1}{3}
$$
$$
r2=\frac{-4}{3}
$$
$$
\text{So we can get y}=c_1e^{\frac{t}{3}}+c_2e^{\frac{-4t}{3}}
$$