Rational numbers correspond to the stores on the number axis one by one. What's wrong

Rational numbers correspond to the stores on the number axis one by one. What's wrong

It's a real number
Some of them are irrational
All rational numbers can be represented by points on the number axis
According to the meaning of the number axis, real numbers and the points on the number axis are corresponding one by one, so all rational numbers can be represented by the points on the number axis, so the answer is correct
All the points on the number axis represent rational numbers______ (judge right or wrong)
The points on the number axis do not necessarily represent rational numbers. For example, the points on the number axis that represent π are not rational numbers, which is wrong
1. The relationship between number axis and rational number: any rational number can be represented by the points on (), but not all the points on the number axis can be represented by (), and it can also be represented by ()
Other numbers, like pi
2. (1) the point on the right of the origin on the number axis represents (), and the point on the left represents ()
(2) Use the point on the right of the origin on the number axis to represent (), use the point on the left of the origin to represent, and use () to represent the zero
(3) For the two numbers represented on the number axis, the number of side () is always larger than that of side ()
(4) The two points which are numbers of each other () are located on both sides of the origin and are equal to () of the origin (the two points are related to each other)
The origin is symmetrical
(5) The reduction of multiple symbols is determined by the number of "-" signs in front of the number. If there are even numbers, the reduction result will be better
If (-) = (-]} is negative, for example, {- 4)}
1. The relationship between number axis and rational number: any rational number can be represented by the points on the number axis, but not all the points on the number axis can be represented by the rational number
Other numbers, like pi
2. (1) on the number axis, the point on the right of the origin represents (positive number), and the point on the left represents (negative number)
(2) The point to the right of the origin on the number axis represents (positive), the point to the left of the origin represents negative, and the zero represents (origin)
(3) The number on the (right) side is always larger than that on the (left) side
(4) The two opposite points are located on both sides of the origin and are equal to the origin (distance) (the two points are relative to each other)
The origin is symmetrical
(5) The reduction of multiple symbols is determined by the number of "-" signs in front of the number. If there are even numbers, the reduction result will be better
If there are (odd number), the reduction result is negative, such as - {+ [- (- 4)]} = - 4
Given that the function f (x) = | lgx | - (1 / 2) x squared has two zeros x1, X2, what is the case of multiplying X1 by x2?
f(x)=7x^2-(k+13)x+k^2-k-2
Parabolic opening upward
It can be seen from the drawing
F (0) 0 K ^ 2-k-20 k-1 or K2
f(1)0 k^2-2k-80 -2k4
F (2) 0 K ^ 2-3k0 K0 or K3
Solution of inequality system-2k-1 or 3k4
It is meaningful to find the known root 2x-6 and simplify X-1 + 3-x
Because of the root 2x-6, 2x-6 is greater than or equal to 0, so x is greater than or equal to 3, so X-1 + 3-x = X-1 + x-3 = 2X-4
For any x1, X2 ∈ (0, + ∞). If f (x) = lgx, try to compare the size of [f (x1) + F (x2)] / 2 and f [(x1 + x 2) / 2]
Please write in detail and easy to understand,
1)f(x1)=lgx1
f(x2)=lgx2
2)[f（x1）+f（x2）]/2=(lgx1+lgx2)/2=(lgx1x2)/2
3)x=(x1+x2)/2
f[（x1+x 2)/2]=lg[(x1+x2)/2]
4)[f（x1）+f（x2）]/2-f[（x1+x 2)/2]
=(lgx1x2)/2-lg[(x1+x2)/2]
=lg[(x1x2)^1/2]-lg[(x1+x2)/2]
5) Lgx is an increasing function, so we only need to compare
(x1x2)^1/2-(x1+x2)/2
[f(x1)+f(x2)]/2=(lgx1+lgx2)/2=
[LG (x1 * x2)] / 2 = X1 * x2 under LG radical
f[(x1+x2)/2]=lg[(x1+x2)/2]
X1, X2 belong to (0, positive infinity)
So (x1 + x2) / 2 is greater than or equal to X1 * x2 under the root sign
And because of lgx increasing function
So f [(x1 + x2) / 2] is greater than or equal to [f (x1) + F (x2)] / 2
Radical 2 (2-radical 2) - radical 8
Root 2 (2-root 2) - root 8 (root 2 + 1) ^ 2 - (root 2-1) ^ 2 (2 times root 54-3 times root 21 + 4 times root 15) * root 3
Radical 2 (2-radical 2) - radical 8 = 2 radical 2 -- 2-2 radical 2 = - 2
(radical 2 + 1) ^ 2 - (radical 2-1) ^ 2 = 2 + 1 + 2 radical 2-2 + 2 radical 2 - 1 = 4 radical 2
(2 times root 54-3 times root 21 + 4 times root 15) * root 3 = (3 times root 6-3 times root 21 + 4 times root 15) * root 3 = 9 root 3-9 root 7 + 12 root 5
It is known that X1 and X2 are the two zeros of the absolute value of the function f (x) = e ^ - x-inx. To find the range of multiplying X1 by x2, please use the combination of numbers and shapes
f(x)=e^（-x）-|lnx|
It's judgment
e^（-x）=|lnx|
The range of X
If you don't understand this question, you can ask. If you are satisfied, remember to adopt it
First simplify and then evaluate: 4 − XX − 2 △ (x + 2 − 12x − 2), where x = 3 − 4
When x = 3 − 4, the original formula = - 13 − 4 + 4 = - 33