The auxiliary equation for the given differential equation has complex roots. Find a general solution. 8y'' -8y' +52y = 0 y(t) =

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**Title: Solving Differential Equations with Complex Roots**

To solve the given differential equation with complex roots, we first recognize the provided equation and proceed with finding the general solution.

**Given Differential Equation:**

\[
8y'' - 8y' + 52y = 0
\]

**Step 1: Auxiliary Equation**

The first step is to formulate the corresponding auxiliary equation. Using the form \(ay'' + by' + cy = 0\), we get the auxiliary equation:

\[
8r^2 - 8r + 52 = 0
\]

**Step 2: Solving the Auxiliary Equation**

Next, solve for roots of the quadratic equation \(8r^2 - 8r + 52 = 0\) using the quadratic formula \(r = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\).

Here, \(a = 8\), \(b = -8\), and \(c = 52\).

Calculate the discriminant:

\[
\Delta = b^2 - 4ac = (-8)^2 - 4(8)(52) = 64 - 1664 = -1600
\]

Since the discriminant \(\Delta\) is less than zero, the roots will be complex. 

Calculate \(r\):

\[
r = \frac{-(-8) \pm \sqrt{-1600}}{2 \cdot 8} = \frac{8 \pm 40i}{16} = \frac{1}{2} \pm \frac{5i}{2}
\]

The complex roots are:

\[
r = \frac{1}{2} \pm \frac{5i}{2}
\]

**Step 3: General Solution**

The general solution to the differential equation with complex roots \(r = \alpha \pm \beta i\), where \(\alpha = \frac{1}{2}\) and \(\beta = \frac{5}{2}\), is:

\[
y(t) = e^{\alpha t} \left( C_1 \cos(\beta t) + C_2 \sin(\beta t) \right)
\]

Substituting \(\alpha\) and \(\beta\):

\[
y(t) = e^{\frac{1}{2} t} \left(
Transcribed Image Text:**Title: Solving Differential Equations with Complex Roots** To solve the given differential equation with complex roots, we first recognize the provided equation and proceed with finding the general solution. **Given Differential Equation:** \[ 8y'' - 8y' + 52y = 0 \] **Step 1: Auxiliary Equation** The first step is to formulate the corresponding auxiliary equation. Using the form \(ay'' + by' + cy = 0\), we get the auxiliary equation: \[ 8r^2 - 8r + 52 = 0 \] **Step 2: Solving the Auxiliary Equation** Next, solve for roots of the quadratic equation \(8r^2 - 8r + 52 = 0\) using the quadratic formula \(r = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\). Here, \(a = 8\), \(b = -8\), and \(c = 52\). Calculate the discriminant: \[ \Delta = b^2 - 4ac = (-8)^2 - 4(8)(52) = 64 - 1664 = -1600 \] Since the discriminant \(\Delta\) is less than zero, the roots will be complex. Calculate \(r\): \[ r = \frac{-(-8) \pm \sqrt{-1600}}{2 \cdot 8} = \frac{8 \pm 40i}{16} = \frac{1}{2} \pm \frac{5i}{2} \] The complex roots are: \[ r = \frac{1}{2} \pm \frac{5i}{2} \] **Step 3: General Solution** The general solution to the differential equation with complex roots \(r = \alpha \pm \beta i\), where \(\alpha = \frac{1}{2}\) and \(\beta = \frac{5}{2}\), is: \[ y(t) = e^{\alpha t} \left( C_1 \cos(\beta t) + C_2 \sin(\beta t) \right) \] Substituting \(\alpha\) and \(\beta\): \[ y(t) = e^{\frac{1}{2} t} \left(
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