The connection and difference between translation and rotation is

The connection and difference between translation and rotation is

Contact: the point moves into a line, the line moves into a surface, and the surface moves into a body
Difference: translation is the movement of an object in a horizontal or vertical direction
Rotation is about a fixed point
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Beijing Normal University Edition, page 16, questions 1 and 2

It is suggested to post the questions one by one in the future, otherwise you can't get the answer if you ask questions like this

How to write the first question of exercise 1.3 on page 15 of Chapter 1 Pythagorean theorem in the eighth grade of mathematics edition of Beijing Normal University How to write the first question of exercise 1.3 (when a truck passes through a tunnel) on page 15 of Chapter 1 Pythagorean theorem in the eighth grade of mathematics edition of Beijing Normal University

There is no way to draw here. You can draw yourself according to what I said. First draw a rectangle (that is, a car), and make a semicircle with the midpoint of one long side of the rectangle as the center and the connecting line between the midpoint and one corner of the rectangle as the radius. It can be seen that the square of the radius is 2.4 square + 1.5 square, and the radius is 2.83

Chapter 5 test questions and answers of Mathematics Grade 7 Volume 1 of Beijing Normal University Edition You need to make a question on the test paper, correct answer and change the question!

I'm afraid it's hard to realize such a wish
Hey!
A waste of time
however
Good luck in the New Year!

A math problem, Beijing Normal University Edition, class hour optimization 13. If the equations 2x + my = 16, x-2y = 0 (binary linear equations), there is a positive integer solution, finding the integer m may obtain all values It's urgent!

Formula 1-2 * 2 = my-4y = 16, get m = 16 / y + 4, and Y and X are positive integers, and x = 2Y. As long as y is an integer, X is an integer, so generation: y = 1,2,4,8,16, get m = 20,12,8,6,5 respectively

Beijing Normal University Edition 15 pages of exploration and innovation Please hurry!

∵√a-1≥0,(ab-2)^2≥0,
√a-1+(ab-2)^2=0
∴a=1,b=2
‡ original formula = 1 / (1 * 2) + 1 / (2 * 3) + 1 / (3 * 4) +.. + 1 / (2005 * 2006)
=1-1/2+1/2-1/3+1/3-1/4+...+1/2005-1/2006
=1-1/2006
=2005/2006
(if anyone plagiarizes my answer, I will destroy you on behalf of the moon!)
P · s: √ stands for root sign* Represents the multiplication sign^ 2 stands for "square of"