Casio calculator interesting game

Interesting calculator knowledge 1. What are the simplest computer common sense?

The function of each key on the keyboard F 1 Help F2 change its name F3 Search F4 Address F5 Refresh F6 Switch F 10 Menu CTRL+A Select All CTRL+C Copy CTRL+X Cut CTRL+V Paste CTRL+Z Undo CTRL+O Open SHIFT+ Delete Delete Delete ALT+ Enter the attribute ALT. +F4 Close CTRL+F4 Close ALT+TAB Switch ALT+ESC Switch ALT+ Spacebar Window Menu CTRL+ESC Start Menu Press CTRL to copy the selected item, press CTRL+SHIFT to create a shortcut when dragging an item, and press SHIFT to stop the CD from playing automatically when inserting the CD into the CD-ROM drive. Turn left to 1, 2, 3. Tab Ctrl+A select all contents of the current page Ctrl+C copy the currently selected contents Ctrl+D open the add favorites panel (add the current page to favorites) Ctrl+E open or close the search sidebar (optional for various search engines) Ctrl+F open the search panel Ctrl+G open or close the simple favorites panel Ctrl+H open the history side. Sidebar Ctrl+I Open Favorites Sidebar/Other: Restore all vertically tiled or horizontally tiled or stacked windows Ctrl+K Close all tabs except the current and locked tabs Ctrl+L Open the Open panel (Iter address or other files can be opened on the current page. Ctrl+N Create a new blank window (you can change it, Maxthon Options → Tags → New) Ctrl+O Open the "Open" panel (you can open the Iter address or other files on the current page. Ctrl+P opens the print panel (you can print web pages, pictures, etc. Ctrl+Q opens the Add to Filter List panel (sends the current page address to the filter list) Ctrl+R refreshes the current page Ctrl+S opens the Save Web Page panel (can save all the contents of the current page) Ctrl+T Tiles all windows vertically Ctrl+V Pastes the contents of the current clipboard Ctrl+W Closes the current tab (window) Ctrl+X Cut when. Previous selection (generally only used for text operation) Ctrl+Y Redo the previous action (generally only used for text operation) Ctrl+Z Undo the previous action (generally only used for text operation) Ctrl+F4 Close the current tab (window) Ctrl+F5 Refresh the current page Ctrl+F6 Switch the tab (window) forward in the chronological order of page opening +F 1 65438+ 0 Hide or display menu bar Ctrl+Tab to switch tabs (windows) down. In small menu mode, Ctrl+ keypad'+'enlarges the current page by 20% Ctrl+ keypad'-'reduces the current page by 20% Ctrl+ keypad' * Restore the zoom of the current page to its original size Ctrl+Shift+ Keypad'+'Enlarge all pages by 20% Ctrl+Shift+ Keypad'-'Reduce all pages by 20% Ctrl+Shift+F Enter the focus and move it to the search bar Ctrl+Shift+G Close the Easy Collection panel Ctrl+Shift+H Open and activate it Shift+W Close all tabs except the locked tab (window Ctrl+Shift+Tab switches tabs (windows) up in the form of small menus. Ctrl+Shift+ Enter the domain name automatically. Alt+ 1 Save the current form Alt+2 as a common form. Alt+A expands the favorites list. The explorer side displays the bottom of the current window. E displays Winver- at the top of the current window-View windows version WinMSD- System information wiaacmgr-Scanner and camera wizard winchat-XP comes with local area network chat wmimgmt.msc-Open the Windows management framework (WMI- WordPad wuaucpl.cpl-Automatically update wupdmgr-Windows updater write WordPad wscript-Windows script host settings wscui.cpl-.

I admire the landlord's question. Does the landlord want to ask about computer maintenance or computer operation?

2. Computer knowledge

Electronic Digital Integrator The first electronic computer was called ENIAC (short for Electronic Digital Integrator and Puter in English), which was born in the United States in February 1946.

Moore's team, which undertakes the development task, consists of four scientists and engineers, namely eckert, Moakley, Goldstein and bocks. Chief engineer eckert is only 24 years old. ENIAC: 30.48m long, width 1 m, floor space170m2, and 30 operation desks, which are about the size of an ordinary room 10. It weighs 30 tons, consumes electricity 150 kw and costs $480,000.

It uses 18000 electron tubes, 70000 resistors, 10000 capacitors, 1500 relays and more than 6000 switches, and carries out 5000 additions or 400 multiplications per second, which is 1000 times that of relay computer and 2000 times that of manual calculation. The idea of developing electronic computers came into being during the Second World War.

At that time, the war was fierce, and the weapons and equipment of various countries were far from what they are now. The main strategic weapons are aircraft and artillery, but there are no Scud missiles, Patriot air defense missiles and Tomahawk cruise missiles. Therefore, it is very necessary and urgent to research and develop new artillery and missiles. To this end, the US Army Ordnance Department established a "Ballistic Research Laboratory" in Aberdeen, Maryland.

The U.S. military requires the laboratory to provide six shooting tables to the army artillery units every day for technical appraisal of missile development. Don't underestimate these six firepower lists, they need amazing workload! In fact, each firepower meter has to calculate hundreds of trajectories, and do you know what the mathematical model of each trajectory is? A set of very complicated nonlinear equations.

These equations cannot be solved accurately, and can only be calculated approximately by numerical methods. But it is not easy to approximate the solution by numerical method! According to the calculation tools at that time, even if the laboratory hired more than 200 calculators to work overtime, it would take about two months to work out a fire list.

In the era of "time is victory", how can such a slow speed work? I'm afraid the defeat will be decided before advanced weapons are developed. In order to change this unfavorable situation, John Moakley, who worked in Moore School of Electrical Engineering at the University of Pennsylvania at that time, put forward the preliminary idea of trial-producing the first electronic computer in 1942, hoping to use electronic tubes instead of relays to improve the calculation speed of the machine.

Upon learning this idea, the US military immediately allocated funds to support it, and set up a research team headed by Mosily and eckert to start research and development, with a budget of $654.38+$5,000, which was a huge sum at that time. If it weren't for the war, who would be willing to pay so much money! Although war is evil, it does not occasionally promote the development of science and technology.

Fortunately for the development work, the mathematician v·n· Weiman (Hungarian-American), who was a consultant of the Ballistics Institute at that time and was participating in the development of the first atomic bomb in the United States, joined the development team halfway through the development process with a large number of calculation problems encountered in the development of the atomic bomb. He made important contributions to solving many key problems of computers, thus ensuring the smooth appearance of computers.

Although ENIAC is huge and consumes amazing power, its operation speed is only several thousand times (the current supercomputer is the fastest, with trillions of operations per second! ), but it is 1000 times faster than the existing computing equipment at that time, and it also has the function of automatically executing arithmetic operation, logical operation and storing data according to pre-programmed programs. ENIAC announced the beginning of a new era.

Since then, the door to scientific computing has also been opened. People will certainly not be satisfied with this! Since the first computer came out, more and more high performance computers have been developed.

Computers have developed from the first generation to the fourth generation, and now they are developing to the fifth and sixth generation intelligent computers. Like ENIAC, many high-performance computers always serve the development of sophisticated and conventional weapons, especially nuclear weapons.

Like all tools invented by human beings, computers are also produced because of practical needs. Since18th century, the level of science and technology has made great progress.

The knowledge of logic circuits and electron tube technology necessary for manufacturing electronic computers appeared and improved at the end of 19 and the beginning of the 20th century. Therefore, it can be said that the basic scientific knowledge of manufacturing computers is complete.

But why did the world's first electronic computer come out in the mid-1940s? This mainly depends on whether the actual demand is urgent and whether the funds are in place. Of course, real needs always exist. Who doesn't want to have a state-of-the-art computing tool? But demand itself is not everything.

When developing a new tool, you always need to invest a lot of money in advance (when developing ENIAC, you initially invested $654.38 +0.5 million, but in the end the total investment was as high as $480,000, which was a huge sum in the 1940s! )。 There are always a few people who can boldly pay for a tool that hasn't come out yet.

Finally, it was the war that made the birth of computers a reality. In fact, among all kinds of social needs, wartime needs are always the most urgent, because it is related to life and death.

* * * The military is always generous, applying the latest scientific and technological achievements to the research and development of strategic and conventional weapons, thus ensuring that it is in a leading position in the military. The electronic computer was developed in the smoke of World War II.

As mentioned above, in order to provide accurate and timely ballistic shooting table for the US military ordnance test, a high-speed calculation tool is urgently needed. Therefore, with the strong support of the US military, 1943 started the development of the world's first electronic computer ENIAC.

Participating in the research and development work is a research team headed by Mosily and eckert from Moore School of Electrical Engineering, University of Pennsylvania. Halfway through the development, the famous mathematician von Neumann joined the ranks.

More than two years later, ENIAC was successfully developed. In the spring of 1945, ENIAC was successfully put into trial operation for the first time.

On February 1946 and 10, the Ordnance Department of the United States Army and Moore College of the University of Pennsylvania jointly announced the birth of ENIAC to the world, which opened the prelude to the development and application of electronic computers. Now people.

3. Know the buttons on the calculator

The meanings of the keys on the calculator are as follows: 1, power on/clear key (ON/AC): press this key to indicate power on or clear the values in all registers.

2. Clear key (c): During digital input, pressing this key for the first time will clear all values except the memory contents. 3. Clear Input Key (CE): Pressing this key during digital input will clear the value in the input register and display "0".

4. Square Root √: displays the square root of the positive input number. 5.M+: put the current display value into the memory; Interrupt digital input.

6.M-: Subtract the currently displayed value from the memory content; Interrupt digital input. 7.MRC: Press this key for the first time to call the memory contents, and press this key for the second time to clear the memory contents.

8.MR: Call the memory contents. 9.MC: Clear the memory contents.

10, GT: press GT key to transfer the contents of GT storage register to display register; Press AC or C to cancel the GT display sign. 1 1, MU (addition and subtraction key): press this key to complete the calculation of interest rate and tax rate.

12, MRC: press this key for the first time to recall the memory content, and press this key for the second time to clear the memory content.

4. How to use the universal calculator

Original publisher: computer black screen 007

How to Use Calculator Calculator Tips Some common functions of ordinary calculators, such as effective calculator and morning light calculator, are believed to have been used by everyone. They are often used to add, subtract, multiply and divide, and calculate results quickly. Some small function keys can get twice the result with half the effort, and many people may never use these functions. I found some information and sorted out the functions and usage of those function keys according to my actual experience. M+: Put the currently displayed value into memory, which is the calculation result, plus the stored number. (If there is no "m" symbol on the screen, that is, there is no data in the memory, the displayed value will be directly stored in the memory. ). M-: Subtract the current displayed value from the memory, which is the calculation result, and subtract the current result from the stored number. If there are no numbers in the memory, press M- to save the negative display number. MS: Store the displayed content in the memory, and the original data in the memory will be washed away. MR: Pressing this key will bring up the contents of the memory, that is, read the value in the memory to the screen and participate in the operation as the current value. MC: Clear the contents of the memory when pressed (the "M" symbol on the screen is deleted). MRC: Pressing this key for the first time will bring up the memory contents, and pressing this key for the second time will clear the memory contents. GT:GT=GrandTotal represents the sum of the total numbers, that is, all the numbers obtained after the equal sign are accumulated and added, and then transferred to the gt storage register. Press GT to display the cumulative number, and then press clear once. MU(Mark-upandMark-down key): press this key to complete the calculation of interest rate and tax rate. See Example 3 for details. CE: clear the input key. Pressing this key during digital input will clear the value in the input register and display "0" for re-input; AC: Yes, clear all data results and operators. ON/C: power-on/clear key, which means to power on or clear the values in all registers when pressed. Example: example 1. Press 32*2 1 first, and the number is 672. Then press

5. Mathematical allusions, numbers, interesting calculations, little knowledge 1 knowledge learned in grade 5 and extracurricular knowledge.

◆ the story of pi1 Zu Chongzhi, the seventh, ranked first in the world, has remained for a thousand years; "The accuracy of calculating pi in a country in history can be used as a symbol to measure the level of mathematical development in that country at that time" (2. 1427, * * * mathematician Al Cassie,16; 1596, Dutch mathematician Rudolf, 35 years old; 1990, with 480 million computers; 65438+February 6, 2002, Tokyo University, 124 1 1 billion.

◆ "0" Roman numeral has no 0; In the fifth century, "0" spread from the East to Rome. At that time, the Pope was very conservative and thought that Roman numerals could be used to remember any number, so "0" was forbidden. A Roman scholar's handbook introduced some usages of 0 and 0, and the Pope tortured them after discovering it. ◆ In the stone statue of an ancient building in Jiaxiang County, Fiona Fang, which is famous for its "rules" and "moments", there are two images of our ancient ancestors deified in ancient times, one is Fuxi and the other is Nu Wa.

The object in Fuxi's hand is a compass, similar to a compass; The object in Nu Wa's hand is called Moment, which is in the shape of a square. China's Ancient Pigeonhole Principle There are many successful examples in China's ancient literature.

For example, in the Song Dynasty Fei Zhou's Records of Liang Man, the pigeon hole principle was used to refute the fallacy of superstitious activities such as "fortune telling". Fei Zhou pointed out that the year, month, day and hour (eight characters) of a person's birth are used as the basis for fortune telling, and the eight characters are used as the "drawer". Only 12 * 360 * 60 = 259200 different drawers.

Taking people in the world as "things", the person who enters the same drawer must be Qian Qian, so the conclusion is that there are many people born at the same time. But since the "eight characters" are the same, "What's the difference between rich and poor?" There are similar words in Qian Daxin's Collection of Thousand Words in Qing Dynasty, Ruan Kuisheng's Tea Guest Talk and Chen Qiyuan's Notes on Yongxianzhai.

But unfortunately, although Chinese scholars have used the pigeon hole principle for the analysis of specific problems for a long time, there is no universal text about the pigeon hole principle in ancient literature, and no one abstracts it as a universal principle. Finally, they had to name this principle after hundreds of years as Dirichlet, a western scholar. The application of pigeon hole principle 1947, Hungarian mathematicians introduced this principle into middle school students' mathematics competition. At that time, there was a question in the Hungarian National Mathematics Competition: "Prove that among any six people, you can find three people who know each other or three people who don't know each other."

At first glance, this question seems incredible. But if you know the principle of pigeon hole, it is very simple to prove this problem.

We use a, b, c, d, e and f to represent six people. Let's choose one of them, such as A, and put the other five people in two drawers: "Know A" and "Don't Know A". According to the pigeon hole principle, there are at least three people in a drawer. Suppose there are three people in the drawer of "Know A". They are b, c and d.

If B, C and D don't know each other, then we have found three people we don't know. If two of B, C and D know each other, for example, B and C know each other, then A, B and C are three people who know each other. In either case, the conclusion of this question is valid.

Because of its novel form and ingenious solution, this test quickly spread all over the world, making many people know this principle. In fact, the pigeon hole principle is not only useful in mathematics, but also plays a role everywhere in real life, such as enrollment, employment arrangement, resource allocation, job title evaluation and so on. It is not difficult to see the function of pigeon cage principle.

Have you ever heard of the question "Chicken and rabbit in the same cage"? This question is one of the famous and interesting questions in ancient China. About 1500 years ago, this interesting question was recorded in Sun Tzu's calculation.

The book describes it like this: "There are chickens and rabbits in the same cage today, with 35 heads on the top and 94 feet on the bottom. The geometry of chicken and rabbit? These four sentences mean: there are several chickens and rabbits in a cage, counting from the top, there are 35 heads; It's 94 feet from the bottom. How many chickens and rabbits are there in each cage? Can you answer this question? Do you want to know how to answer this question in Sunzi Suanjing? The answer is this: If you cut off the feet of every chicken and rabbit in half, then every chicken will become a "one-horned chicken" and every rabbit will become a "two-legged rabbit".

In this way, the total number of feet of (1) chickens and rabbits changed from 94 to 47. (2) If there is a rabbit in the cage, the total number of feet is more than the total number of heads 1. So the difference between the total number of feet 47 and the total number of heads 35 is the number of rabbits, that is, 47-35= 12 (only).

Obviously, the number of chickens is 35- 12=23. This idea is novel and strange, and its "foot-cutting method" has also amazed mathematicians at home and abroad.

This way of thinking is called reduction. Reduction method means that when solving a problem, we do not directly analyze the problem first, but deform and transform the conditions or problems in the problem until it is finally classified as a solved problem.

Pucsok's interesting topic Pucsok is a famous mathematician in the former Soviet Union. 195 1 wrote a book, Math Teaching Methods in Primary Schools.

There is an interesting question in this book. This shop sold 1026 meter cloth in three days.

The sales volume of the second day is twice that of the first day; On the third day, it sold three times as much as the next day. How much rice cloth do you want to sell in three days? The problem can be thought of this way: the number of meters sold on the first day is regarded as 1 serving.

You can draw the following line chart: the first day 1 copy; The second day is twice as much as the first day; The third day is three times that of the second day and two times that of the first day. Comprehensive calculation shows that the number of cloth sold on the first day is1026 ÷ (l+2+6) =1026 ÷ 9 =114 (meters) and1/kloc-.

Please do the problem in this way. Four people donated money for disaster relief.

B donated twice as much as A, C donated three times as much as B, D donated four times as much as C, and they donated 132 yuan.

How much do you want each of the four people to donate? There was a general named Han Xin in the Han Dynasty. Every time he * * * troops, he only asked his men to count off at l~3, 1~5, 1~7, and then reported the remainder of each team's count off, so he knew how many people had arrived.

His ingenious algorithm is called "Ghost Valley Calculation", "Partition Calculation" or "Han Xin Point Soldiers", which is also called by foreigners.