Questions about high school math sets 10

Supplements).

2.From a b = to obtain b set in a-3 = -3, 2 a-1 =

3, a2+1=-3, the solution is a=0 or -1Substituting a=0 into the set of a and b has a=, b=, then a b=, which contradicts a b=, so a=0 is not appropriate. In the same way, substituting a=-1 into the set of a and b fits the title, so the value of the real number a is -1.

3。(1) From b=, b= can be obtained. From a b=b, we get a=, a=, a=, a=, a=, and a=empty sets.

When taking a=, it means that there are two different solutions to the equation 1 and 2 in a, and using Veda's theorem, then p,q satisfies the condition of 1+2=-p, 1*2=q, and p=-3, q=2;

When taking a=, it means that there are two identical solutions to the equation in a1, using Veda's theorem, then p,q satisfies the condition for .

1+1=-p,1*1=q,get p=-2,q=1;

When a= is taken, it means that there are two identical solutions to the equation 2 in a, and using Veda's theorem, then p,q satisfies the condition for .

2+2=-p,2*2=q,p=-4,q=4;

When a=empty set is taken, indicating that there is no solution to the equation in a, then p,q satisfies the condition =b 2-4ac=p 2-4q<0, that is, p 2<4q

2）a∩r*= ？, less conditional.

The combination symbol can't be typed.,Use words:

1. P-union (the complement of q in u).

2、a=-1

3、(1)p=-2,q=1; or p=-4,q=4; or p=-3,q=2; or p2-4q<0

The third question and the second question are incomplete and cannot be answered.

A set that doesn't contain any elements is called an empty set and is denoted (as shown below, I don't make it big). For example, if the equation x 6 0 has no solution in the range of real numbers, that is, the solution set is an empty set, the common intersection of two parallel lines, and the triangle whose sum is less than the third side are all empty sets.

But 0 is not an empty set, it is a set with an element 0, also known as a single element set, 0.

Problem 1: There is a set of x -2x+1=0, because in fact, the root of the number is solved, x1=1, x2=1. According to the heterogeneity of the elements (that is, each element that makes up the set should be different from each other, and the elements in the set cannot be repeated, that is, only one of the same can be counted.

If the set representation is wrong, the correct representation is. ）

So, there is only one set of all the real roots of this equation, ie.

Question 3: Certainty, that is, any object in nature is not the elements of this set is unambiguous, either it is or it is not. Such as:

An integer larger than 4 can form a set, 5 is the element of the set, and 3 is not an element of the set, it is very clear that there is no ambiguous element.