1. Multiple choice questions (3 points for each question, * * * 24 points)
The value of 1. Equal to ()
The third century BC.
2. In the number-1.4 14, π, 3. , 2+, 3.2 122 1 …, 3. 14, the number of irrational numbers is ().
A.5 B.2 C.3 D.4
3. The following conclusions are known: ① Only irrational numbers can be represented on the number axis; ② Any irrational number can be represented by a point on the number axis; ③ Real numbers correspond to points on the number axis one by one; ④ Rational numbers are infinite and irrational numbers are limited. The correct conclusion is ().
A.①② B.②③ C.③④ D.②③④
4. The following calculation is correct ()
a、B、C、D、
5. In the following statement, () is incorrect.
The arithmetic square root of A 3 is the square root of B 3 is.
C-3 is the arithmetic square root of D. -3 is the cube root of D.
6. If both A and B are real numbers and satisfy │ A-2 │+= 0, then the value of B-A is
A. 2b. 0c-2d. None of the above is true.
7. If it is -3, the value range of is ().
A.> 3 B. ≥3 C.