Calc Help: Solving Differential Equation y'' + y' - 6y=0 with e^(rt)

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To solve the differential equation y'' + y' - 6y = 0 using the function y = e^(rt), the first and second derivatives of y must be calculated. The first derivative is y' = re^(rt) and the second derivative is y'' = r^2e^(rt). Substituting these derivatives into the differential equation leads to the characteristic equation r^2 + r - 6 = 0. Factoring this equation reveals the values of r that satisfy the original differential equation are r = 2 and r = -3. The solution to the differential equation is thus expressed in terms of these values of r.
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Calc Help!

For what values of r does the function y= e^(rt) satisfy the differential equation y'' + y' - 6y=0
 
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Find the first derivative of of y(t) and its second derivative then use those values in the differential equation. The rest should be obvious!
 
Remember that e^(rt) can never equal 0.
 
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