Question: do an integral example
1. **Problem Statement:** Calculate the integral $$\int (3x^2 + 2x + 1) \, dx$$.
2. **Formula Used:** The integral of a polynomial term $$ax^n$$ is given by $$\int ax^n \, dx = \frac{a}{n+1}x^{n+1} + C$$, where $$C$$ is the constant of integration.
3. **Step-by-step Solution:**
- Break the integral into separate terms:
$$\int (3x^2 + 2x + 1) \, dx = \int 3x^2 \, dx + \int 2x \, dx + \int 1 \, dx$$
- Integrate each term:
$$\int 3x^2 \, dx = 3 \int x^2 \, dx = 3 \cdot \frac{x^{2+1}}{2+1} = 3 \cdot \frac{x^3}{3}$$
- Simplify by canceling common factors:
$$3 \cdot \frac{x^3}{\cancel{3}} = \cancel{3} \cdot \frac{x^3}{3} = x^3$$
- Next term:
$$\int 2x \, dx = 2 \int x \, dx = 2 \cdot \frac{x^{1+1}}{1+1} = 2 \cdot \frac{x^2}{2}$$
- Simplify by canceling common factors:
$$2 \cdot \frac{x^2}{\cancel{2}} = \cancel{2} \cdot \frac{x^2}{2} = x^2$$
- Last term:
$$\int 1 \, dx = x$$
4. **Combine all results:**
$$x^3 + x^2 + x + C$$
5. **Final Answer:**
$$\int (3x^2 + 2x + 1) \, dx = x^3 + x^2 + x + C$$
This shows how to integrate a polynomial by applying the power rule term-by-term and simplifying.