√28 =
2√7
≈ 5.291503
Square root of 28 — 5.291503 (2√7)
Irrational
The square root of 28 is about 5.291503, or exactly 2√7. It lies between 5 and 6.
- As a decimal
- ≈ 5.291503
- Simplified surd
- √28 = 2√7
- Between
- 5 < √28 < 6
- Squared
- 28² = 784
- Cube root
- ∛28 ≈ 3.036589
How the surd is simplified
Pull out the largest square factor. Since 50 = 25 × 2, the root of 25 comes out as 5 and the 2 stays behind: 5√2.
√28 = √(4 × 7) = 2√7
Nearby numbers
From 1 to 200
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How to read this
- The decimal is rounded; the surd form is the exact value.
- Pulling out a square factor simplifies the surd — √50 = 5√2.
- If the number is not a perfect square, the decimal never ends (irrational).
- Knowing which two integers it sits between is enough to estimate in your head.
Frequently asked questions
Q. What is the square root of 28?
About 5.291503, or exactly 2√7.
Q. Can the surd be simplified?
Yes: 28 = 4 × 7, so 2 comes out and it becomes 2√7.
Q. Between which integers does it fall?
Between 5 and 6.
Q. What is the cube root of 28?
About 3.036589.