√293 at a glance
- Exact value
- √293
- Decimal (10 places)
- 17.1172427686
- Rounded
- 17.1 · 17.12 · 17.117
- Perfect square?
- No — between 17² and 18²
- Rational?
- Irrational
- Both square roots
- ±17.117243
- Prime factorization
- 293
- Cube root
- 6.641852
How to simplify √293
293 is a prime number, so its only factors are 1 and 293. There is no perfect-square factor to pull out, which means √293 is already in its simplest radical form.
The square root of any prime is irrational. If √293 were a fraction a/b in lowest terms, then a² = 293b², so 293 would divide a — and then 293 would divide b too, contradicting “lowest terms.” That is why the decimal 17.1172427686 is only a rounded value.
Where √293 sits between perfect squares
289 = 17² and 324 = 18² are the nearest perfect squares, so √293 lies between 17 and 18. 293 is 4 above 289 and 31 below 324, so the root is closer to 17.
- Straight line between 289 and 324: 17.1143 (0.02% low)
- Tangent from 17, i.e. 17 + 4 ÷ 34: 17.1176 (0% high)
- Tangent from 18, i.e. 18 − 31 ÷ 36: 17.1389 (0.13% high)
For √293 the tangent at 17 wins, missing by only 0.0004. Tangent estimates shine when the number sits close to a perfect square — here 293 is just 4 above 289.
Finding √293 with the Babylonian method
This is Newton’s method applied to f(x) = x² − 293: following the tangent line down to zero simplifies to averaging x with 293 ÷ x.
Start from the nearest whole number, 17 (17² = 289):
| Step | Guess x | 293 ÷ x | Average | Correct decimals |
|---|---|---|---|---|
| 1 | 17.0000000000 | 17.2352941176 | 17.1176470588 | 3 |
| 2 | 17.1176470588 | 17.1168384880 | 17.1172427734 | 8 |
| 3 | 17.1172427734 | 17.1172427638 | 17.1172427686 | 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 √293 = 17.1172427686 to every decimal shown.
√293 as a continued fraction
Every irrational square root has a continued fraction that repeats. For √293 the pattern is [17; 8, 1, 1, 8, 34] with the block of 5 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √293 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 |
|---|---|---|
| 17/1 | 17.0000000000 | 1.2 × 10⁻¹ |
| 137/8 | 17.1250000000 | 7.8 × 10⁻³ |
| 154/9 | 17.1111111111 | 6.1 × 10⁻³ |
| 291/17 | 17.1176470588 | 4.0 × 10⁻⁴ |
| 2,482/145 | 17.1172413793 | 1.4 × 10⁻⁶ |
| 84,679/4,947 | 17.1172427734 | 4.8 × 10⁻⁹ |
The same fractions solve Pell’s equation, x² − 293y² = 1. Its smallest solution in positive whole numbers is x = 12,320,649, y = 719,780. Because the period is odd, the equation with −1 on the right also has a solution: 2,482² − 293 × 145² = −1.
√293 in geometry and everyday measurements
- A square patio or deck of 293 square feet is about 17.12 ft (17 ft 1 in) on each side, so edging all the way around takes 4 × √293 ≈ 68.5 ft.
- 293 = 2² + 17², so by the Pythagorean theorem √293 is the diagonal of a 2 × 17 rectangle — and the distance between the points (0, 0) and (2, 17) on a grid.
Square roots near √293 and related roots
| Root | Simplest form | Decimal | Perfect square? |
|---|---|---|---|
| √290 | √290 | 17.0294 | No |
| √291 | √291 | 17.0587 | No |
| √292 | 2√73 | 17.0880 | No |
| √293 | √293 | 17.1172 | No |
| √294 | 7√6 | 17.1464 | No |
| √295 | √295 | 17.1756 | No |
| √296 | 2√74 | 17.2047 | No |
- The cube root of 293 is about 6.641852.
- Squaring undoes the root: (√293)² = 293, while 293² = 85,849 — the number whose square root is 293.
Frequently asked questions
What is the square root of 293?
The square root of 293 is √293, about 17.1172427686. The negative root, −17.117243, also squares to 293.
Is the square root of 293 rational or irrational?
Irrational. 293 is not a perfect square — it falls between 289 and 324 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.
Can √293 be simplified?
No. 293 is prime, so there is no perfect square to take out of the radical.
What is √293 rounded to two decimal places?
√293 ≈ 17.12 to two decimal places (17.1 to one, 17.117 to three). Check: 17.12² = 293.0944, close to 293.