√132 at a glance
- Exact value
- 2√33
- Decimal (10 places)
- 11.4891252931
- Rounded
- 11.5 · 11.49 · 11.489
- Perfect square?
- No — between 11² and 12²
- Rational?
- Irrational
- Both square roots
- ±11.489125
- Prime factorization
- 2² × 3 × 11
- Cube root
- 5.091643
How to simplify √132
Look for the largest perfect square that divides 132. Here it is 4 (2²), because 132 = 4 × 33 and 33 has no square factor left:
The prime factorization tells the same story: 132 = 2² × 3 × 11. Each pair of equal primes leaves the radical as one factor, so 2 comes out and 3 × 11 stays inside.
Check: (2√33)² = 2² × 33 = 4 × 33 = 132. As a decimal, 2√33 = 2 × 5.7445626465 ≈ 11.4891252931.
Where √132 sits between perfect squares
121 = 11² and 144 = 12² are the nearest perfect squares, so √132 lies between 11 and 12. 132 is 11 above 121 and 12 below 144, so the root is closer to 11.
- Straight line between 121 and 144: 11.4783 (0.09% low)
- Tangent from 11, i.e. 11 + 11 ÷ 22: 11.5000 (0.09% high)
- Tangent from 12, i.e. 12 − 12 ÷ 24: 11.5000 (0.09% high)
For √132 the straight-line estimate is the closest of the three. The straight line always undershoots and the tangents always overshoot, because the square-root curve bends downward; near the middle of the gap the undershoot is smaller.
Finding √132 with the Babylonian method
Picture a rectangle with an area of 132 and one side x; the other side must be 132 ÷ x. Averaging the two sides gives a rectangle that is closer to a square, and the side of that square is exactly √132.
Start from the nearest whole number, 11 (11² = 121):
| Step | Guess x | 132 ÷ x | Average | Correct decimals |
|---|---|---|---|---|
| 1 | 11.0000000000 | 12.0000000000 | 11.5000000000 | 1 |
| 2 | 11.5000000000 | 11.4782608696 | 11.4891304348 | 5 |
| 3 | 11.4891304348 | 11.4891201514 | 11.4891252931 | all 10 shown |
The count of correct decimals went 1, 5 and all 10 over 3 steps — roughly doubling each time — until the guess matched √132 = 11.4891252931 to every decimal shown.
√132 as a continued fraction
Every irrational square root has a continued fraction that repeats. For √132 the pattern is [11; 2, 22] with the block of 2 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √132 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 |
|---|---|---|
| 11/1 | 11.0000000000 | 4.9 × 10⁻¹ |
| 23/2 | 11.5000000000 | 1.1 × 10⁻² |
| 517/45 | 11.4888888889 | 2.4 × 10⁻⁴ |
| 1,057/92 | 11.4891304348 | 5.1 × 10⁻⁶ |
| 23,771/2,069 | 11.4891251812 | 1.1 × 10⁻⁷ |
| 48,599/4,230 | 11.4891252955 | 2.4 × 10⁻⁹ |
The same fractions solve Pell’s equation, x² − 132y² = 1. Its smallest solution in positive whole numbers is x = 23, y = 2.
√132 in geometry and everyday measurements
- A square room or garden bed covering 132 square feet measures about 11.49 ft (11 ft 6 in) along each wall.
- 132 is not a sum of two whole-number squares — the prime factor 3 and 11 (one less than a multiple of 4) appears an odd number of times, which rules that out — so √132 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 2 × 8 × 8 box, because 2² + 8² + 8² = 132.
- Since √132 = 2√33, a length of √132 is exactly 2 copies of the length √33 laid end to end.
Square roots near √132 and related roots
| Root | Simplest form | Decimal | Perfect square? |
|---|---|---|---|
| √129 | √129 | 11.3578 | No |
| √130 | √130 | 11.4018 | No |
| √131 | √131 | 11.4455 | No |
| √132 | 2√33 | 11.4891 | No |
| √133 | √133 | 11.5326 | No |
| √134 | √134 | 11.5758 | No |
| √135 | 3√15 | 11.6190 | No |
- The cube root of 132 is about 5.091643.
- Four times the radicand doubles the root: √528 = 2 × √132 ≈ 22.978251.
Frequently asked questions
What is the square root of 132?
The square root of 132 is 2√33 in simplest radical form, which is about 11.4891252931. The negative root, −11.489125, also squares to 132.
Is the square root of 132 rational or irrational?
Irrational. 132 is not a perfect square — it falls between 121 and 144 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.
Can √132 be simplified?
Yes. The largest perfect square dividing 132 is 4, so √132 = √4 × √33 = 2√33.
What is √132 rounded to two decimal places?
√132 ≈ 11.49 to two decimal places (11.5 to one, 11.489 to three). Check: 11.49² = 132.0201, close to 132.