Math.sqrt()Math.sqrt() 静态方法返回数字的平方根。那是 ¥The Math.sqrt() static method returns the square root of a number. That is ∀ x ≥ 0 , 𝙼𝚊𝚝𝚑.𝚜𝚚𝚛𝚝 ( 𝚡 ) = x = the unique y ≥ 0 such that y 2 = x \forall x \geq 0,;\mathtt{\operatorname{Math.sqrt}(x)} = \sqrt{x} = \text{the unique } y \geq 0 \text{ such that } y^2 = x Try it 语法¥Syntax jsMath.sqrt(x) 参数¥Parameters x 大于或等于 0 的数字。 返回值¥Return value x 的平方根,一个非负数。如果是 x < 0,则返回 NaN。 ¥The square root of x, a nonnegative number. If x < 0, returns NaN. 描述¥Description 因为 sqrt() 是 Math 的静态方法,所以你始终将其用作 Math.sqrt(),而不是用作你创建的 Math 对象的方法(Math 不是构造函数)。 ¥Because sqrt() is a static method of Math, you always use it as Math.sqrt(), rather than as a method of a Math object you created (Math is not a constructor). 示例¥Examples 使用 Math.sqrt()¥Using Math.sqrt() jsMath.sqrt(-1); // NaN Math.sqrt(-0); // -0 Math.sqrt(0); // 0 Math.sqrt(1); // 1 Math.sqrt(2); // 1.414213562373095 Math.sqrt(9); // 3 Math.sqrt(Infinity); // Infinity 规范SpecificationECMAScript Language Specification # sec-math.sqrt¥Specifications 浏览器兼容性BCD tables only load in the browser with JavaScript enabled. Enable JavaScript to view data.¥Browser compatibility 也可以看看¥See also Math.cbrt() Math.exp() Math.log() Math.pow()