√792 at a glance
- Exact value
- 6√22
- Decimal (10 places)
- 28.1424945589
- Rounded
- 28.1 · 28.14 · 28.142
- Perfect square?
- No — between 28² and 29²
- Rational?
- Irrational
- Both square roots
- ±28.142495
- Prime factorization
- 2³ × 3² × 11
- Cube root
- 9.252130
How to simplify √792
Look for the largest perfect square that divides 792. Here it is 36 (6²), because 792 = 36 × 22 and 22 has no square factor left:
The prime factorization tells the same story: 792 = 2³ × 3² × 11. Each pair of equal primes leaves the radical as one factor, so 2 × 3 comes out and 2 × 11 stays inside.
792 has 3 square factors (4, 9 and 36). Starting with a smaller one still works but takes more rounds: √792 = 2√198, and √198 can be simplified again. Using 36 straight away finishes in one step.
Check: (6√22)² = 6² × 22 = 36 × 22 = 792. As a decimal, 6√22 = 6 × 4.6904157598 ≈ 28.1424945589.
Where √792 sits between perfect squares
784 = 28² and 841 = 29² are the nearest perfect squares, so √792 lies between 28 and 29. 792 is 8 above 784 and 49 below 841, so the root is closer to 28.
- Straight line between 784 and 841: 28.1404 (0.01% low)
- Tangent from 28, i.e. 28 + 8 ÷ 56: 28.1429 (0% high)
- Tangent from 29, i.e. 29 − 49 ÷ 58: 28.1552 (0.05% high)
For √792 the tangent at 28 wins, missing by only 0.0004. Tangent estimates shine when the number sits close to a perfect square — here 792 is just 8 above 784.
Finding √792 with the Babylonian method
Picture a rectangle with an area of 792 and one side x; the other side must be 792 ÷ x. Averaging the two sides gives a rectangle that is closer to a square, and the side of that square is exactly √792.
Start from the nearest whole number, 28 (28² = 784):
| Step | Guess x | 792 ÷ x | Average | Correct decimals |
|---|---|---|---|---|
| 1 | 28.0000000000 | 28.2857142857 | 28.1428571429 | 3 |
| 2 | 28.1428571429 | 28.1421319797 | 28.1424945613 | 8 |
| 3 | 28.1424945613 | 28.1424945566 | 28.1424945589 | all 10 shown |
The count of correct decimals went 3, 8 and all 10 over 3 steps — roughly doubling each time — until the guess matched √792 = 28.1424945589 to every decimal shown.
√792 as a continued fraction
Every irrational square root has a continued fraction that repeats. For √792 the pattern is [28; 7, 56] with the block of 2 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √792 is irrational.
Cutting the continued fraction off early gives the best fractions for approximating the root — no fraction with a smaller denominator comes closer:
| Fraction | Decimal | Error |
|---|---|---|
| 28/1 | 28.0000000000 | 1.4 × 10⁻¹ |
| 197/7 | 28.1428571429 | 3.6 × 10⁻⁴ |
| 11,060/393 | 28.1424936387 | 9.2 × 10⁻⁷ |
| 77,617/2,758 | 28.1424945613 | 2.3 × 10⁻⁹ |
| 4,357,612/154,841 | 28.1424945589 | < 10⁻¹⁰ |
| 30,580,901/1,086,645 | 28.1424945589 | < 10⁻¹⁰ |
The same fractions solve Pell’s equation, x² − 792y² = 1. Its smallest solution in positive whole numbers is x = 197, y = 7.
√792 in geometry and everyday measurements
- 792 square feet is 73.6 m². Laid out as a square — a small house footprint or a lot — it is about 28.14 ft (28 ft 2 in) on a side.
- 792 is not a sum of two whole-number squares — the prime factor 11 (one less than a multiple of 4) appears an odd number of times, which rules that out — so √792 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 2 × 2 × 28 box, because 2² + 2² + 28² = 792.
- Since √792 = 6√22, a length of √792 is exactly 6 copies of the length √22 laid end to end.
Square roots near √792 and related roots
| Root | Simplest form | Decimal | Perfect square? |
|---|---|---|---|
| √789 | √789 | 28.0891 | No |
| √790 | √790 | 28.1069 | No |
| √791 | √791 | 28.1247 | No |
| √792 | 6√22 | 28.1425 | No |
| √793 | √793 | 28.1603 | No |
| √794 | √794 | 28.1780 | No |
| √795 | √795 | 28.1957 | No |
- The cube root of 792 is about 9.252130.
- Because 792 = 4 × 198, the root is twice √198: 2 × 14.071247 ≈ 28.142495.
Frequently asked questions
What is the square root of 792?
The square root of 792 is 6√22 in simplest radical form, which is about 28.1424945589. The negative root, −28.142495, also squares to 792.
Is the square root of 792 rational or irrational?
Irrational. 792 is not a perfect square — it falls between 784 and 841 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.
Can √792 be simplified?
Yes. The largest perfect square dividing 792 is 36, so √792 = √36 × √22 = 6√22.
What is √792 rounded to two decimal places?
√792 ≈ 28.14 to two decimal places (28.1 to one, 28.142 to three). Check: 28.14² = 791.8596, close to 792.