Derivative Exponential Sine
1. Stating the problem: Find the derivative of the function $$f(x)=e^{3x} \sin(\ln(9+x))$$.
2. Use the product rule for differentiation: if $$f(x)=u(x)v(x)$$, then $$f'(x)=u'(x)v(x)+u(x)v'(x)$$.
3. Let $$u(x)=e^{3x}$$ and $$v(x)=\sin(\ln(9+x))$$.
4. Differentiate $$u(x)=e^{3x}$$ using the chain rule: $$u'(x) = e^{3x} \cdot 3 = 3e^{3x}$$.
5. Differentiate $$v(x)=\sin(\ln(9+x))$$ using the chain rule:
- The outer function is $$\sin(z)$$ where $$z=\ln(9+x)$$, so $$\frac{d}{dx}[\sin(z)] = \cos(z) \cdot z'$$.
- The inner function is $$z=\ln(9+x)$$, so $$z' = \frac{1}{9+x}$$.
Thus, $$v'(x) = \cos(\ln(9+x)) \cdot \frac{1}{9+x}$$.
6. Substitute $$u', u, v'$$ into the product rule:
$$f'(x) = 3e^{3x} \sin(\ln(9+x)) + e^{3x} \cdot \cos(\ln(9+x)) \cdot \frac{1}{9+x}$$.
7. Factor if desired:
$$f'(x) = e^{3x} \left(3 \sin(\ln(9+x)) + \frac{\cos(\ln(9+x))}{9+x}\right)$$.
Final answer:
$$f'(x) = e^{3x} \left(3 \sin(\ln(9+x)) + \frac{\cos(\ln(9+x))}{9+x}\right)$$