The poems of Li Shangyin, a poet of Tang Dynasty, show that new things can't be stopped, and the wonderful thing is that () The poem () teaches people to be positive, good and good. The same is true

The poems of Li Shangyin, a poet of Tang Dynasty, show that new things can't be stopped, and the wonderful thing is that () The poem () teaches people to be positive, good and good. The same is true

Li Shangyin, a poet of the Tang Dynasty, wrote a poem (thousands of sails pass by the side of a sunken boat and thousands of trees spring in front of a diseased tree)
Poetry (want to be poor for thousands of miles, to a higher level.) educates people to be positive, better and better. The same is true

The poem says that new things can't be stopped, and the same is true----------

After the Yangtze River waves push ahead, the new people in the world catch up with the old people

What poems show that new things can't be stopped? What poems are similar to them

The waves behind the Yangtze River push the waves ahead, and the new people in the world catch up with the old people
Thousands of sails pass by the side of the sunken boat and thousands of trees spring in front of the diseased tree
The new leaves in the forest urge the old leaves, and the flowing water makes the former waves give way to the latter

Simple calculation of 13 / 9 * 11 / 7 + 13 / 7 * 11 / 2
9 / 13 * 7 / 11 + 7 / 13 * 2 / 11
Simple calculation
Did not understand, had better give next step

Original formula: 13 / 9 * 11 / 7 + 13 / 7 * 11 / 2 adjustment order
It can be changed to: 13 * 11 / 7 / 9 + 13 * 11 / 7 / 2,
Then 13 * 11 / 7 is extracted to be 13 * 11 / 7 (1 / 9 + 1 / 2)

Sequence {an}, A1 = 1,2a (n + 1) = an + 1, find the general term an?

2a2=a1+1
So A2 = 1
In the same way
a3=a4=a5=…… =1
So an = 1

The floor of a room should be paved with square bricks. For example, 480 square bricks with an area of 9 square decimeters are needed. If the square bricks with an area of 16 square decimeters are used instead, how many are needed

480x9/16=270

What do 56 nationalities and 56 flowers associate with?
More Braille,

National harmony and unity

How to calculate Sin & # 178; 45 ° + cos & # 178; 60 ° =
Why is it equal to 3 / 4

You don't have to pay special attention to this. Just replace it
Because sin45 = √ 2 / 2
cos60=1/2
simple form
=(√2/2)^2+(1/2)^2
=1/2+1/4
=3/4

The length of three sides of a right triangle is 3cm, 4cm and 5cm respectively. The area of the right triangle is () square decimeter

0.3×0.4÷2=0.06

1. If there is only one element in the solution set of the equation AX ^ 2 + 2x + a = 0, where a ∈ R, then the value range of real number a is_________ .
2. The elements of set a are composed of solutions of KX ^ 2-3x + 2 = 0, where k ∈ R. if there is at most one element in a, the range of K value can be obtained
3. The elements of set a are composed of x = a + B √ 2 (a ∈ Z, B ∈ z). Judge the relationship between the following elements x and set a: 0,1 / (√ 2-1), 1 / (√ 3 - √ 2)
4. Given that the element X in the set P satisfies: X ∈ n, and 2 ＜ x ＜ a, and there are exactly three elements in the set P, then the integer a=________ .
5. If x ∈ R, set a represents a set of elements in 3, x, x ^ 2-2x, then what conditions should x satisfy?

1. Because a ∈ R, it can be divided into two cases: (1) when a = 0, x = 0, it is consistent; (2) when a is not equal to 0, if there is only one solution to the quadratic equation, it can be judged as 0, that is, 4-4a * a = 0, the solution is a = 1 or - 1. In conclusion, a = 0,1, - 1