若 x, y 都是实数, 且 y = $$\sqrt[]{x-4}+\sqrt[]{4-x}+9$$ , 则 y 的平方根是 ( )

二次根式 $$\frac{1}{\sqrt[]{x-1}}$$ 中, x 的取值范围是

已知 a, b 为实数, 且 a = $$\sqrt[]{b-8}-\sqrt[]{8-b}+25$$ 则 $$\sqrt[]{a}+\sqrt[3]{b}$$ 的值为 ( )

下列各式中, 不一定是二次根式的是 ( )

已知 a, b, c 在数轴上的位置如图所示, 化简 $$\sqrt[]{\left(b-a\right)^2}-\left|a-c\right|-\sqrt[]{b^2}$$ 为

下列二次根式中, 不是最简二次根式的是 ( )

Which of the following quadratic radical is the simplest quadratic radical?

Which of the following quadratic radical is the simplest quadratic radical?

In the following algebraic expressions: $$\sqrt{\frac{\pi}{3}}$$ , $$\sqrt{27a}$$ , $$\sqrt{42}$$ , $$\frac{1}{\sqrt{0.7}}$$ , $$-\sqrt{(x^2-y^2)(x+y)}$$ , $$\sqrt[3]{5^2}$$ , $$\sqrt{x^2 + y^2}$$ How many are the simplest quadratic radicals?

Among the following expressions: ①√3, ②√(1/4), ③√9, ④√0.5, ⑤√11, how many are the simplest quadratic radicals?

Which of the following calculations is incorrect?

把 $$（1-x）\sqrt[]{\frac{1}{x-1}}$$ 根号外面的因式移到根号内得（ ）

Calculate √3 × √9, the result is:

Calculate: $$6\sqrt[]{7}\times\frac{1}{3}\sqrt[]{21}\div2\sqrt[]{3}$$ . The result is ( )

Which of the following calculations is correct?

If a = $$2+\sqrt[]{5}$$ , b = $$\frac{1}{2-\sqrt[]{5}}$$ , then the relationship between a and b is ( )

25的平方根是（ ）

Which of the following expressions is the simplest quadratic radical?

下列各数中，与 $$2\sqrt[]{3}$$ 的乘积为有理数的是（　　）

Which of the following simplification results is incorrect?

23. $$\frac{1}{\sqrt{3} - \sqrt{5}} = ( )$$

Given $$a = \sqrt{7} + 2$$ , $$b = \frac{3}{\sqrt{7} - 2}$$ , then the relationship between $$a$$ and $$b$$ is ( )