Answer:
f(x + h) = 3x³ + x² + 9h²x + 3h³ + h² + 9hx² + 2hx
General Formulas and Concepts:
- Order of Operations: BPEMDAS
- Distributive Property
- Expand by FOIL (First Outside Inside Last)
- Combining like terms
Step-by-step explanation:
Step 1: Define function
f(x) = x² + 3x³
f(x + h) is x = x + h
Step 2: Simplify
- Substitute: f(x + h) = (x + h)² + 3(x + h)³
- Expand by FOILing: f(x + h) = (x² + 2hx + h²) + 3(x + h)³
- Rewrite: f(x + h) = (x² + 2hx + h²) + 3(x + h)²(x + h)
- Expand by FOILing: f(x + h) = (x²+2hx+h²) + 3(x² + 2hx + h²)(x+h)
- Distribute/Expand: f(x + h) = (x²+2hx+h²) + 3(x³+3hx²+3h²x+h³)
- Distribute 3: f(x + h) = (x²+2hx+h²)+(3x³+9hx²+9h²x+3h³)
- Combine like terms: f(x + h) = 3x³+x²+9h²x+3h³+h²+9hx²+2hx
