Example 1
- a = 3
- b = 4
49
What is (3 + 4)²? 49. 9 + 24 + 16.
Square of a sum
Type a and b. The square of a sum of two terms is (a + b)², expanded as a² + 2ab + b². 3 and 4 give 49. 2 and 2 give 16. 1 and 0 give 1.
The calculator does not call power on the sum. It computes a*a + 2*a*b + b*b. 3 and 4 give 49, the same as 7².
Results
Enter data and click Calculate.
How it works
The square of a sum of two terms is (a + b)². School expands that to a² + 2ab + b². With 3 and 4 you have 9 + 24 + 16 = 49. The calculator does not raise the sum in one call: it multiplies a*a + 2*a*b + b*b.
The fields are a and b. Order does not change the result: 4 and 3 also give 49, because 16 + 24 + 9 = 49. 2 and 2 give 16, because 4 + 8 + 4. That is (2 + 2)².
When b = 0, only a² remains. 1 and 0 give 1. When a = 0, only b² remains. A minus in a term passes: (−1) and 4 give 9, because (−1 + 4)² = 9.
Difference of squares is on the neighbouring page and computes (a − b)(a + b), not the square of a sum. A power with exponent 2 raises one number, not a sum of two fields.
The header units switch does not multiply anything. 3 and 4 stay 49 whatever the label says.
3 and 4 give 49. 2 and 2 give 16. 1 and 0 give 1. That is the whole card: two terms and an expanded square.
Formula
(a + b)² = a² + 2ab + b²
How to use
- Type a and b, for example 3 and 4.
- Click Calculate. The square of the sum comes out 49.
- 2 and 2 give 16. 1 and 0 give 1.
- The order of a and b does not change the result.
- Difference of squares lives on the neighbouring card.
3 and 4 give 49
The square of a sum is a² + 2ab + b². 3 and 4 give 49. 2 and 2 give 16. 1 and 0 give 1.
- square
- The second power of the sum. 3 and 4 give 49. 2 and 2 give 16.
- sum
- Two terms a and b. The calculator expands (a + b)². It does not subtract.
- terms
- Fields a and b. When b = 0, a² remains and 1 and 0 give 1.
Examples
Example 2
- a = 2
- b = 2
16
What is (2 + 2)²? 16. 4 + 8 + 4.
Example 3
- a = 1
- b = 0
1
What is (1 + 0)²? 1. Only a² remains.
Related calculators
Common questions
What is (3 + 4)²?
49. 9 + 24 + 16. The calculator multiplies a*a + 2*a*b + b*b.
What does square of a sum mean?
(a + b)² expanded as a² + 2ab + b². Two terms, one square.
What do 2 and 2 give?
16. That is (2 + 2)². 4 + 8 + 4.
What do 1 and 0 give?
1. When b = 0, a² remains.
Does the order of a and b change the result?
No. 3 and 4 and 4 and 3 both give 49.
Does a negative a pass?
Yes. (−1) and 4 give 9, because (−1 + 4)² = 9.
How is this different from difference of squares?
Here (a + b)². There (a − b)(a + b). Another formula, the paired card.
Does the calculator call power?
Not on the sum. It adds three products.
Where is the power of one number?
On the power page. Here you always have two terms.
Does a comma in 3.5 work?
Yes. 3.5 and 3,5 are the same decimal.
Knowledge sources
The calculator computes the same formula as the definition below.
Page updated in 2026.