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Verify that the indicated function is an explicit solution of the given differential equation. Assume an appropriate interval I of definition for the solution.

By' +y=0; y e-x/8
When y = e-x/8,
y'--8
Thus, in terms of x,
Sy' + y =
0
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We have the DE,
y'+y=0, verify that
y=e^{(-x)/(8)} is a solution.

We have,
y=e^{(-x)/(8)}, find
y'.

=>
y'=(-1)/(8) e^{(-x)/(8)}

Plug
y and
y' into the DE.

=>
y'+y=0

=>
((-1)/(8) e^{(-x)/(8)})+(e^{(-x)/(8)})=0

=>
e^{(-x)/(8)}=(1)/(8) e^{(-x)/(8)}

=>
e^{(-x)/(8)}\\eq (1)/(8) e^{(-x)/(8)}

Thus,
y=e^{(-x)/(8)}, is not a solution to the given DE.

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