1. **State the problem:** Evaluate the definite integral of the function $6x^2 + 5$ from $x=1$ to $x=3$.
2. **Formula and rules:** The definite integral of a function $f(x)$ from $a$ to $b$ is given by
$$\int_a^b f(x)\,dx = F(b) - F(a)$$
where $F(x)$ is the antiderivative of $f(x)$.
3. **Find the antiderivative:** For $f(x) = 6x^2 + 5$, the antiderivative is
$$F(x) = \int (6x^2 + 5)\,dx = 2x^3 + 5x + C$$
where $C$ is the constant of integration.
4. **Evaluate the definite integral:**
$$\int_1^3 (6x^2 + 5)\,dx = F(3) - F(1) = (2(3)^3 + 5(3) + C) - (2(1)^3 + 5(1) + C)$$
5. **Simplify:**
$$= (2 \times 27 + 15 + C) - (2 \times 1 + 5 + C)$$
$$= (54 + 15 + C) - (2 + 5 + C)$$
$$= 69 + C - 7 - C$$
6. **Cancel constants:**
$$= 69 - 7 = 62$$
**Final answer:**
$$\boxed{62}$$
Definite Integral 1E4813
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