1. **Problem:** Given functions $f(x) = 3x - 5$ and $g(x) = 7x + 2$, find each combined function and state any domain restrictions.
2. **Formula and rules:**
- Addition: $(f+g)(x) = f(x) + g(x)$
- Subtraction: $(f-g)(x) = f(x) - g(x)$
- Multiplication: $(f \cdot g)(x) = f(x) \times g(x)$
- Division: $\left(\frac{f}{g}\right)(x) = \frac{f(x)}{g(x)}$, with domain restriction $g(x) \neq 0$
3. **Step a: Addition**
$$(f+g)(x) = (3x - 5) + (7x + 2)$$
Combine like terms:
$$= 3x + 7x - 5 + 2 = 10x - 3$$
No domain restrictions since polynomials are defined for all real $x$.
4. **Step b: Subtraction**
$$(f-g)(x) = (3x - 5) - (7x + 2)$$
Distribute the minus:
$$= 3x - 5 - 7x - 2 = (3x - 7x) + (-5 - 2) = -4x - 7$$
No domain restrictions.
5. **Step c: Multiplication**
$$(f \cdot g)(x) = (3x - 5)(7x + 2)$$
Use FOIL:
$$= 3x \times 7x + 3x \times 2 - 5 \times 7x - 5 \times 2$$
$$= 21x^2 + 6x - 35x - 10$$
Combine like terms:
$$= 21x^2 - 29x - 10$$
No domain restrictions.
6. **Step d: Division**
$$\left(\frac{f}{g}\right)(x) = \frac{3x - 5}{7x + 2}$$
Domain restriction: denominator $\neq 0$
$$7x + 2 \neq 0 \implies 7x \neq -2 \implies x \neq -\frac{2}{7}$$
**Final answers:**
- $(f+g)(x) = 10x - 3$, domain all real numbers
- $(f-g)(x) = -4x - 7$, domain all real numbers
- $(f \cdot g)(x) = 21x^2 - 29x - 10$, domain all real numbers
- $\left(\frac{f}{g}\right)(x) = \frac{3x - 5}{7x + 2}$, domain $x \neq -\frac{2}{7}$
Function Operations C8B06E
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