EXPRESSION
Definition Of Expression
An Expression is a mathematical phrase that combines numbers and/or variables using mathematical operations.
An expression is a representation of a value; for example, variables and/or numerals that appear alone or in combination with operators are expressions.
Video Examples: Expression in Maths
Example of Expression
The following are a few mathematical expressions.
5 + 6 - (3 + 2)/18
a + b - c
7 + 34
log3 (x + 1) + log3 (x - 3)
Solved Example on Expression
Ques: Evaluate the expression for x = 1.
2x2 + (x + 1)(x - 1) + 2(x - 3)
Choices:
A. - 2
B. 2
C. 0
D. 1
Correct Answer: A
Solution:
Step 1: Substitute x = 1 in the expression 2x2 + (x + 1)(x - 1) + 2(x - 3) and then simplify.
Step 2: = 2 + 0 + (- 4)
Step 3: = - 2
Quick Summary
- An expression combines numbers and variables with operators.
- Expressions represent values.
- Expressions do not contain an equals sign (=).
🍎 Teacher Insights
Emphasize the difference between expressions and equations. Use visual aids to illustrate the order of operations. Provide plenty of practice problems with varying levels of complexity.🎓 Prerequisites
- Basic Arithmetic
- Variables
- Order of Operations
Check Your Knowledge
Q1: Which of the following is an expression?
Q2: Evaluate the expression 2x + 1 for x = 3
Frequently Asked Questions
Q: What is the difference between an expression and an equation?
A: An expression represents a value, while an equation shows that two expressions are equal.
Q: Can an expression contain only numbers?
A: Yes, an expression can contain only numbers (e.g., 5 + 3) or a combination of numbers and variables (e.g., 2x + 1).