Scenery observation composition 450 words,

I love the campus in winter. With the falling snowflakes and the cold air, she, the girl in winter, quietly comes to the third school of Jinchuan company. At the gate of the school, the girl sprinkles a layer of slippery crystal ice, which makes the teachers and students slide and enjoy themselves. Walking into the campus, the teaching building is frozen

The composition of the fourth unit of the fifth grade Chinese volume I is 500 words

Winter is coming, snowflakes are flying like goose feathers
Early in the morning, I walk in the street, feel very cold
The day before yesterday, the city ordered that all kinds of advertisements and leaflets posted in any corner should be cleaned up. For this reason, all the cleaners in the city started to clean the beautiful city
I watched the snow flying all over the sky and a group of cleaners busy
Inadvertently, I found a smooth wall on the opposite side was pasted with some leaflets and other papers. An old woman cleaner was tearing the papers carefully. It seemed that the papers were hard to tear. The woman cleaner brushed the papers with a wet brush and then carefully tore them with her hands
I think her hands must be cold, but she is not afraid of cold
She was very serious and cleaned several pieces of paper in succession
She went to another one
But when I saw her right hand raised, it stopped in the air and seemed to freeze. Then I saw her body close to the wall. Then I saw her shaking her head slightly
What's the matter? What's the matter? I'm surprised
I saw her focus for a while, then slowly left the paper, did not clear it
Why not clear it? Did she forget the city rules? A series of questions floated in my mind
Well, I'll go over and have a look, I think
As like as two peas in the street, I was just beginning to see another little cleaner coming closer to the paper. She acted like the old cleaner. She raised her right hand and fixed it in the air. She shook her head slightly, and watched it for a moment, and slowly left.
I was more confused and determined to have a look
After crossing the road, I came to the front of the wall. What caught my eyes was a notice for people. It said: Zhao Jie, female, 14 years old
I finally understood everything
Snowflakes are still flying like goose feathers, but I don't feel cold anymore

Grade 5 Volume 1 unit 1 composition, 500 words

First of all, the composition should be original in conception, and the writing should be a little different in taste
In writing, we should write down our true feelings. In the beginning, we can't do without reference and imitation. But what really moves people's hearts is our painstaking creation,
Everyone has read. Gorky said: "books are the ladder of human progress. I love reading more than mice love rice. Books are my eternal fruit and my spiritual wealth."
When I was a child, I couldn't read. Those small and black words were a new world for me. My parents bought me many fairy tale books from childhood. There were many illustrations in those books. Although I didn't know what they were, I loved the gorgeous colors on the picture whenever I saw them. When I saw my parents reading, I imitated them. Finally, I was fascinated, When I was in grade one or two, there were enough books at home to make a pile of hills. After school at noon every day, I always took my favorite one hundred thousand whys home and looked at it with relish. I always read this book until I could recite it, I know why the sky is blue? Why the grass is green? Why the sun is round and so on
3、 When I was in the fourth grade, my taste of reading improved again, and I began to read some classic fairy tales. I had read Andersen's fairy tales, oz fairy tales, Green's fairy tales and so on. When I saw the tense fragments, my heart was raised. When the danger was over, the joy of victory came, I cheered unconsciously. Whenever I roam in the sea of books, I feel how small my knowledge is
5、 When I was in grade six, my taste of reading became higher and higher. I began to read widely. I ate more and more, as if I could not finish it. Whenever I went out to talk with others, I always felt like I had changed a person
I love books. Every time I finish my homework, I must spend two or three hours to read. I remember once, when I was reading in bed, I was seeing the wonderful part. Suddenly, the light was turned off, and the room was dark. It was my mother. She kindly said, "little book fan, good sleep." "mother, my good mother, let me watch it for another 30 minutes." my mother allowed me, When I finished reading this story, I was attracted by another story. Thirty minutes passed quickly. I pretended to be asleep first, and my mother left satisfied. After my mother left, I secretly turned on the light and began to enjoy it again. In this way, I didn't go to sleep until I finished reading all the contents of the book
Books give me happiness, let me know a lot of truth. I love reading!
You can give it to me!

Find the special solution y '= (y ^ 2-2xy-x ^ 2) / (y ^ 2 + 2xy-x ^ 2) y | x = 1 = 1 of the following differential equation satisfying the initial condition
（x+y)(x^2+y^2)=4x^2

This problem is the second solution of differential equation in advanced mathematics textbook. The right numerator denominator of homogeneous equation is divided by x ^ 2 to get: y '= [(Y / x) ^ 2-2 (Y / x) - 1] / [(Y / x) ^ 2 + 2 (Y / X) - 1] let Y / x = u, y = Xu, y' = u + Xu ', then the original equation is transformed into: U + Xu' = [u ^ 2-2u-1] / [u ^ 2 + 2u-1] and sorted out as: X (DU / DX) = - (U ^ 3 + u ^ 2 +

It is known that a * A-6A + 9 and absolute value B-1 are opposite numbers, then the value of formula (A / B-B / a) / (a + b) is（

(a^2-6a+9)+|b-1|=0
(a-3)^2+|b-1|=0
So A-3 = 0, B-1 = 0
a=3,b=1
(a/b-b/a)/(a+b)=(3-1/3)/4=2/3

Judgment: two multiplication and two division problems can be calculated with the same formula

Yes, multiplication

1. Right hand rule in the three-dimensional coordinate system, the positive axis direction of Z axis is determined according to the right-hand rule. The right-hand rule also determines any coordinate in the three-dimensional space
1. Right hand rule
In the three-dimensional coordinate system, the positive direction of Z axis is determined according to the right-hand rule. The right-hand rule also determines the positive rotation direction of any coordinate axis in the three-dimensional space
To mark the positive direction of X, y and Z axes, put your right hand back to the screen, and point your thumb to the positive direction of X axis. Extend your index finger and middle finger. The index finger points to the positive direction of Y axis, and the direction indicated by the middle finger is the positive direction of Z axis
To determine the positive rotation direction of the axis, as shown in the figure on the right, use the thumb of the right hand to point to the positive direction of the axis and bend the finger. Then the direction indicated by the finger is the positive rotation direction of the axis
What does it mean to place your right hand away from the screen?

The palm of the hand is toward you, the back of the hand is toward the computer

Given that α is the second quadrant angle and Tan α = - 43, find the value of sin (α + π 4) sin 2 α + cos 2 α + 1

∵ Tan α = - 43, and α is the second quadrant, ∵ cos α = − 35 (4) sin (α + π 4) sin2 α + Cos2 α + 1 = 22sin α + 22cos α 2Sin α cos α + 2cos2 α = 224cos α = 24cos α = - 5212 (12 points)

How to use brackets in the article?
For example, I have used a bracket () in a sentence for supplementary explanation. How can I use a word in the bracket sentence if I need to put another bracket on it?
Are they all in parentheses, or are they just like math?
2L, parentheses in math, parentheses I know
But in Chinese articles, if brackets are used in parentheses, do they all use parentheses directly? I mean, if the brackets are parentheses, do you want the outside brackets to be brackets or braces?

This is simple. Continue to use brackets. Really, I have noticed this problem. Later, I found that the professor of mathematics group of Tongji University used it in this way. It should be right!

Who can solve these math problems
log4 16 ×log9 8=?
3^(2+log32)=?
5^(2-log5 3)=?

1.log4 (16) ×log9( 8)
=log2^2(2^4)*log3^2(2^3)
=2log2 (2)*3/2log2(3)
=2*3/2log2(3)
=3log2(3)
2.3^(2+log32)
=3^2*3^log3(2)
=9*2
=18
3.5^(2-log5 3)
=5^2/5^log5(3)
=25/3

Scenery observation composition 450 words,