์ํ
์ฆ์, ๋น๊ณต๊ฐ, ๋ฌด๋ฃ
์ ๊ณฑ๊ทผ ๊ณ์ฐ๊ธฐ.
โ72 = 6โ2์ ๊ฐ์ด ์ด๋ค ์์ ์ ๊ณฑ๊ทผ์ ์์ ๋ฐ ๋จ์ํ๋ ๊ทผํธ ํํ๋ก ๊ตฌํ์ธ์.
๊ฐ์ ์ ๋ ฅํ์ธ์
์ ๋ ฅํ๋ ๋์ ๊ฒฐ๊ณผ๊ฐ ์ ๋ฐ์ดํธ๋ฉ๋๋ค.
์ฌ์ฉ ๋ฐฉ๋ฒ
The square root of a number is the value that multiplies by itself to give that number. 12 x 12 = 144, so the square root of 144 is 12.
Simplified radical form pulls the largest perfect-square factor out from under the radical sign: โ72 = โ(36 x 2) = 6โ2. It is the exact answer, unlike a rounded decimal.
Negative numbers have no real square root, so this calculator asks for a number of 0 or more. Decimals are supported but are only shown as a decimal answer, not as a radical.
์์ฃผ ๋ฌป๋ ์ง๋ฌธ
How do you simplify a square root?
Find the largest perfect square that divides the number, then take its root outside the radical. For โ72, the largest perfect-square factor is 36, so โ72 = โ(36 x 2) = 6โ2. Simplified radical form is exact, unlike a rounded decimal such as 8.485.
What is a perfect square?
A perfect square is a number whose square root is a whole number, because it is some integer multiplied by itself: 1, 4, 9, 16, 25, 36, 49, 64, 81, 100 and so on. When you enter one, this calculator flags it and the radical disappears entirely โ โ144 is simply 12.
Why is โ72 equal to 6โ2?
72 factors as 36 x 2, and 36 is a perfect square. Since โ(a x b) = โa x โb, you get โ36 x โ2 = 6โ2. Stopping at 4 x 18 would give 2โ18, which is correct but not fully simplified โ always pull out the largest perfect square.
Can you take the square root of a negative number?
Not within the real numbers: any real number multiplied by itself is zero or positive, so nothing squares to a negative. Mathematicians define imaginary numbers for this (โ-9 = 3i), but this calculator works in real numbers and asks for an input of 0 or more.
What is the square root of 0 and of 1?
Both are perfect squares and are their own square roots: โ0 = 0 because 0 x 0 = 0, and โ1 = 1 because 1 x 1 = 1. They are the only two numbers that equal their own square root.
Can I enter decimals?
Yes. The decimal square root is calculated for any non-negative number, so โ2.25 = 1.5. Radical simplification is only shown for whole numbers, because pulling perfect-square factors out of a decimal has no standard simplified form.