A calculus problem by Rocco Dalto

Calculus Level pending

$\begin{cases} \dfrac{dx}{dt} = 3x - 2y - 3z \\ \dfrac{dy}{dt} = x + 2y - 3z \\ \dfrac{dz}{dt} = x - z \end{cases}$



The general solution to the above differential system is as follows:

$\begin{cases} x(t) = c_{1}x_{1}(t) + c_{2}x_{2}(t) + c_{3}x_{3}(t) \\ y(t) = c_{1}y_{1}(t) + c_{2} y_{2}(t) + c_{3}y_{3}(t) \\ z(t) = c_{1}z_{1}(t) + c_{2}z_{2}(t) + c_{3}z_{3}(t) \end{cases}$ where $\begin{vmatrix}{x_{j}(t)} \\{y_{j}(t)} \\ {z_{j}(t)} \\ \end{vmatrix} = \begin{vmatrix}{A_{j}} \\{B_{j}} \\ {C_{j}} \\ \end{vmatrix} * e^{\lambda_{j} t}$

for $$(1 <= j <= 3)$$.



If $$C_{1} = 1, \: C_{2} = 1, \: C_{3} = 1$$ and $$x(0) = 1$$, $$y(0) = 2$$, and $$z(0) = 3$$. Find $$c_{1} + c_{2} + c_{3}$$.



$$Hint:$$ The eigenvalues are $$\lambda_{1} \in \mathbb{R}$$ and $$\lambda_{2}, \lambda_{3} = a \pm bi$$.

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