The example of applying Pythagorean theorem in daily life is urgent! ! ! ! (10! ! ! ! )

Update 1: sorry ar, I don't want to be a joke, and I don't understand it! ! I want to use the example of P

The example of applying Pythagorean theorem in daily life is urgent! ! ! ! (10! ! ! ! )

Update 1: sorry ar, I don't want to be a joke, and I don't understand it! ! I want to use the example of Pythagorean theorem in daily life to understand ga easily!

Update 2: Sorry ar, I don't want to be a joke, and I can't understand it! ! I want to use the example of Pythagorean theorem in daily life to understand ga easily!

Pythagorean theorem can be calculated from cosine law to cosine law.

we know

(a^2)=(b^2)+(c^2)-2(b)(c)(cosa)(a^2)=(b^2)+(c^2)-2(b)(c)(cos90)(a^2)=(b^2)+(c^2)-2(b)(c)(0)(a^2)=(b^2)+(c^2)& amp； lt； -Pythagoras Theorem Pythagoras discovered Pythagoras Theorem, also known as quotient height theorem. The quotient height theorem refers to the sum of squares of two sides of a right triangle = the ratio of three sides of the hypotenuse of a square isosceles triangle is 1: 1: the root number is 2. In China's ancient books, Pythagorean theorem is also called ". The word "hook string" comes from the names of three sides of a regular triangle: "hook" is a shorter stock; "Shares" are longer shares; "Chord" refers to the hypotenuse. China's Pythagorean method is used to discover astronomy and measure geography. According to another symbolic ancient mathematical classic of China, Pian Jing of Zhou Pian, as early as the early China (about 2 100 BC), China mathematicians gave a special proof of the 3-4-5 triangle in Pythagorean theorem. The Pythagorean chapter of Nine Chapters of Arithmetic has 24 questions, which are divided into two parts. The first part focuses on the right triangle operation centered on Pythagorean theorem, and the second part is related to Pythagorean measurement. In Liu Hui's Nine Arithmetic Notes, the development process from Pythagorean Theory to Proportional Theory is clearly recorded, and the theoretical system of Pythagorean String Theory is completely and strictly explained. The following will focus on the proof of Pythagorean theorem proposed by Liu Hui. Liu Hui used the problem of finding the hypotenuse length of a right triangle with two known strands of 3 and 4 as an introduction, and then generalized and proved the Pythagorean theorem. His proof is as follows: (1) Choose any right triangle; (2) Make two squares with hooks and ropes; (3) placing two squares side by side; (4) Divide two squares into one square and four right triangles with hooks. We can easily find that these four triangles are congruent with the original triangle, as shown in figure 1. (5) Move the two right-angled triangles on the outside to the square with the chord as the side, as shown in Figure 2. (6) We can get a complete square of the chord and prove that (hook) 2+ (chord) 2 = (chord) 2. In fact, the above two diagrams contain another important hook-strand-chord relationship: (chord) 2 = 2 (Pythagorean product)+(Pythagorean difference) 2. A2+B2 = C2' This is the most famous discovery of the Greek scholar Pythagoras: Pythagoras & # 39; Theorem, namely "quotient height theorem" and "Pythagorean theorem"). This theorem explains the relationship between the three sides of a right triangle: "The square of the hypotenuse is equal to the sum of the squares of the other two sides. Because there are too many ways to prove Pythagorean theorem, I only give two examples of China in the Three Kingdoms period for your reference. During the Three Kingdoms period, Zhao Shuang, a mathematician from the State of Wu, made an annotation for Zhou Li Parallel Computing. He annotated the Pythagorean Theorem in Zhou Kuaishu's Jing Zhu. He wrote an article about Pythagorean square diagram, and attached a second Pythagorean square diagram (see figure), which proved Pythagorean theorem: make a square with chords as its sides, and its area is called "chord reality". Draw four right triangles in that square and color them with vermilion. This area is called "Zhu Shi". The small square in the middle is painted yellow, and its area is called "yellow". The side length of a small square is equal to the difference between the strand and the hook. But "string reality" is equal to the sum of four "Zhu reality" and "Huang reality". So it is concluded that chord 2 = 4. [0.5 (hook. Stock)]+(stock hook) 2 strings 2 = 2 (hook. Shares)+hook 2 Chord 2 = hook 2+share 2 Two daily applications of Pythagorean theorem (answered in the form of jokes): Take a right triangle as an example, the two right angles are 3m and 4m respectively, and the hypotenuse is 5m. Because 3 2+4 2 = 5 2, there are two daily applications: one is to estimate the distance between two places. A: (on mobile phone) I want you to go to the second phase of the national finance. You go to Queensway Square? Isn't it? Can I fly from home to Lebanon? A: Oh dear! I have a map broadcast. Look at it first ... _ _ _ We are separated by 4 squares and 3 squares horizontally, that is, the distance is 5 squares. _ _ _ Each grid is175m, that is, the distance is 875m. . _ _ _ Run 800 meters over Lebanon. Fly "yes" ! Want jam! What's the temperature in central Lebanon? b:？ ? ! ... well, in a hurry to bury me? . (Take-up) 2 Consideration of storing extra-long objects Son: Ama? What a beautiful fishing rod! Why don't you buy me? . Mom: The pole is 5 feet long and the room is thin, so there is no place to put it! Son: Put it in the cupboard. Mom: A locker is 4 feet high. Why don't you put it down? Wang: A storage cabinet is 4 feet high and 3 feet deep. These poles are not five feet long. _ _ _ According to Pythagorean theorem, it can be obliquely attached to the edge of the buried cabinet, which is good for the shelf! Mom: (dripping with sweat)? ……? !

The leveling staff on the construction site (that is,' Mo Dou guy') needs to draw a pair of vertical lines on the ground for construction/measurement, and the principle of 3-4-5 is Pythagorean Theorem (that is, Pythagorean Theorem). This is why the general automatic ruler is 5m long. 2006-11-24 00: 20: 28 supplement: the automatic ruler is a tool for leveling staff to draw and check on the ground.

Two daily applications of Pythagorean theorem (in the form of jokes) Pythagorean theorem: in a right triangle, the square of the hypotenuse is equal to the sum of the squares of two right angles. For example, the two right angles are 3m and 4m respectively, and the hypotenuse is 5m. Because 3 2+4 2 = 5 2, there are two daily applications: 1. Estimate the distance between the two places A: (on mobile phone) I want to invite you to the "National Finance Phase II". Are you going to Queensway Square? Isn't it? Can I fly from home to Lebanon? A: Hey! I have a map broadcast. Look at it first ... _ _ _ We are separated by 4 squares and 3 squares horizontally, that is, the distance is 5 squares. _ _ _ Each grid is175m, that is, the distance is 875m. . _ _ _ Run 800 meters over Lebanon. Fly "yes" ! Want jam! What's the temperature in central Lebanon? b:？ ? ! ... well, in a hurry to bury me? . (receiving) 2. Precautions for storing very long objects: Ama,? What a beautiful fishing rod! Why don't you buy me? . Mom: The pole is 5 feet long and the room is thin, so there is no place to put it! Son: Put it in the cupboard. Mom: A locker is 4 feet high. Why don't you put it down? Wang: A storage cabinet is 4 feet high and 3 feet deep. These poles are not five feet long. _ _ _ According to Pythagorean theorem, it can be obliquely attached to the edge of the buried cabinet, which is good for the shelf! Mom: (dripping with sweat) (&; #39; #_#)