√236 at a glance
- Exact value
- 2√59
- Decimal (10 places)
- 15.3622914957
- Rounded
- 15.4 · 15.36 · 15.362
- Perfect square?
- No — between 15² and 16²
- Rational?
- Irrational
- Both square roots
- ±15.362291
- Prime factorization
- 2² × 59
- Cube root
- 6.179747
How to simplify √236
Look for the largest perfect square that divides 236. Here it is 4 (2²), because 236 = 4 × 59 and 59 has no square factor left:
The prime factorization tells the same story: 236 = 2² × 59. Each pair of equal primes leaves the radical as one factor, so 2 comes out and 59 stays inside.
Check: (2√59)² = 2² × 59 = 4 × 59 = 236. As a decimal, 2√59 = 2 × 7.6811457479 ≈ 15.3622914957.
Where √236 sits between perfect squares
225 = 15² and 256 = 16² are the nearest perfect squares, so √236 lies between 15 and 16. 236 is 11 above 225 and 20 below 256, so the root is closer to 15.
- Straight line between 225 and 256: 15.3548 (0.05% low)
- Tangent from 15, i.e. 15 + 11 ÷ 30: 15.3667 (0.03% high)
- Tangent from 16, i.e. 16 − 20 ÷ 32: 15.3750 (0.08% high)
For √236 the tangent at 15 wins, missing by only 0.0044. Tangent estimates shine when the number sits close to a perfect square — here 236 is just 11 above 225.
Finding √236 with the Babylonian method
Picture a rectangle with an area of 236 and one side x; the other side must be 236 ÷ x. Averaging the two sides gives a rectangle that is closer to a square, and the side of that square is exactly √236.
Start from the nearest whole number, 15 (15² = 225):
| Step | Guess x | 236 ÷ x | Average | Correct decimals |
|---|---|---|---|---|
| 1 | 15.0000000000 | 15.7333333333 | 15.3666666667 | 2 |
| 2 | 15.3666666667 | 15.3579175705 | 15.3622921186 | 6 |
| 3 | 15.3622921186 | 15.3622908729 | 15.3622914957 | all 10 shown |
The count of correct decimals went 2, 6 and all 10 over 3 steps — roughly doubling each time — until the guess matched √236 = 15.3622914957 to every decimal shown.
√236 as a continued fraction
Every irrational square root has a continued fraction that repeats. For √236 the pattern is [15; 2, 1, 3, 5, 1, 6, 1, 5, 3, 1, 2, 30] with the block of 12 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √236 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 |
|---|---|---|
| 15/1 | 15.0000000000 | 3.6 × 10⁻¹ |
| 31/2 | 15.5000000000 | 1.4 × 10⁻¹ |
| 46/3 | 15.3333333333 | 2.9 × 10⁻² |
| 169/11 | 15.3636363636 | 1.3 × 10⁻³ |
| 891/58 | 15.3620689655 | 2.2 × 10⁻⁴ |
| 1,060/69 | 15.3623188406 | 2.7 × 10⁻⁵ |
The same fractions solve Pell’s equation, x² − 236y² = 1. Its smallest solution in positive whole numbers is x = 561,799, y = 36,570.
√236 in geometry and everyday measurements
- A square patio or deck of 236 square feet is about 15.36 ft (15 ft 4 in) on each side, so edging all the way around takes 4 × √236 ≈ 61.4 ft.
- 236 is not a sum of two whole-number squares — the prime factor 59 (one less than a multiple of 4) appears an odd number of times, which rules that out — so √236 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 2 × 6 × 14 box, because 2² + 6² + 14² = 236.
- Since √236 = 2√59, a length of √236 is exactly 2 copies of the length √59 laid end to end.
Square roots near √236 and related roots
| Root | Simplest form | Decimal | Perfect square? |
|---|---|---|---|
| √233 | √233 | 15.2643 | No |
| √234 | 3√26 | 15.2971 | No |
| √235 | √235 | 15.3297 | No |
| √236 | 2√59 | 15.3623 | No |
| √237 | √237 | 15.3948 | No |
| √238 | √238 | 15.4272 | No |
| √239 | √239 | 15.4596 | No |
- The cube root of 236 is about 6.179747.
- Four times the radicand doubles the root: √944 = 2 × √236 ≈ 30.724583.
Frequently asked questions
What is the square root of 236?
The square root of 236 is 2√59 in simplest radical form, which is about 15.3622914957. The negative root, −15.362291, also squares to 236.
Is the square root of 236 rational or irrational?
Irrational. 236 is not a perfect square — it falls between 225 and 256 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.
Can √236 be simplified?
Yes. The largest perfect square dividing 236 is 4, so √236 = √4 × √59 = 2√59.
What is √236 rounded to two decimal places?
√236 ≈ 15.36 to two decimal places (15.4 to one, 15.362 to three). Check: 15.36² = 235.9296, close to 236.