Questions: Find a general solution to the given equation for t<0.
y''(t) - (3/t) y'(t) + (29/t^2) y(t) = 0
Transcript text: Find a general solution to the given equation for $\mathrm{t}<0$.
\[
y^{\prime \prime}(t)-\frac{3}{t} y^{\prime}(t)+\frac{29}{t^{2}} y(t)=0
\]
Solution
Solution Steps
To solve the given differential equation, we recognize it as a Cauchy-Euler equation. The general approach involves assuming a solution of the form \( y(t) = t^m \) and substituting it into the differential equation to find the characteristic equation. Solving the characteristic equation will give us the values of \( m \), which we use to construct the general solution.
Step 1: Characteristic Equation
We start with the characteristic equation derived from the assumption \( y(t) = t^m \):
\[
m(m - 1) - 3m + 29 = 0
\]
This simplifies to:
\[
m^2 - 4m + 29 = 0
\]
Step 2: Solve for \( m \)
Using the quadratic formula \( m = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \), we find the roots:
\[
m = \frac{4 \pm \sqrt{(-4)^2 - 4 \cdot 1 \cdot 29}}{2 \cdot 1} = \frac{4 \pm \sqrt{16 - 116}}{2} = \frac{4 \pm \sqrt{-100}}{2}
\]
This gives us:
\[
m = 2 \pm 5i
\]
Step 3: General Solution
Since the roots are complex, the general solution for the differential equation is given by:
\[
y(t) = t^2 \left( C_1 \cos(5 \ln |t|) + C_2 \sin(5 \ln |t|) \right)
\]
where \( C_1 \) and \( C_2 \) are arbitrary constants.
Final Answer
The general solution is:
\[
\boxed{y(t) = t^2 \left( C_1 \cos(5 \ln |t|) + C_2 \sin(5 \ln |t|) \right)}
\]