Answer:
See explanation.
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Algebra I
- Functions
- Function Notation
Calculus
Limits
- Right-Side Limit: 
  
- Left-Side Limit: 
  
Limit Rule [Variable Direct Substitution]: 

Explanation:
Step 1: Define
Identify

Step 2: Find Right Limit
- Substitute in variables [Right-Side Limit]: 
  
- Evaluate limit [Limit Rule - Variable Direct Substitution]: 
  
- Subtract: 
  
∴ the right-side limit equals 2.
Step 3: Find Left Limit
- Substitute in variables [Left-Side Limit]: 
  
- Evaluate limit [Limit Rule - Variable Direct Substitution]: 
  
- [√Radical] Add: 
  
- [√Radical] Evaluate: 
  
∴ the left-side limit equals 2.
Step 4: Find Limit
The right and left-side limits are equal.
∴ 

Topic: AP Calculus AB/BC (Calculus I/I + II)
Unit: Limits
Book: College Calculus 10e