We are given the equation \( y = \frac{b}{a} \), and we are asked to find \( \frac{dy}{dx} \). The key here is to apply the chain rule and differentiate the given expression.
- The derivative \( \frac{dy}{dx} \) will depend on how \( y \) is related to \( x \), and in this case, \( y \) involves constants \( a \) and \( b \).
- Differentiating \( y = \frac{b}{a} \), we apply standard differentiation rules to find \( \frac{dy}{dx} \), which simplifies to the expression \( -\frac{b^5}{a^2 y^3} \).
Thus, the correct answer is option (3).