[Social Talk] Elementary Arithmetics(四則演算)
Arithmetic, arithmetic, and arithmetic, the four basic operations of addition, subtraction, multiplication, and division is called.
In the past, it was called "Kakamseungje(加減乘除)", and included arithmetic operations as kanji.
Some people who know math well know that some people put exponents and parentheses in the place of division and division.
I do not know exactly what it means, because subtraction is a negative addition and division is a multiplication involving a negative exponent.
So, what would be the priority in arithmetic operations?
What should we do first when we have addition, subtraction, multiplication, and division?
The order is as follows.
Calculate from inside the parentheses, if the inner parentheses are repeated, count from the innermost parentheses.
Computes multiplication and division.
Computes addition and subtraction.
If you have multiplication and division / addition and subtraction operations, you can calculate from left to right.
The same applies for parentheses.
How was this order determined?
In fact, it is because it is.
That's all we can say, but according to Infix notation, the notation we use.
Prefix notation and Postfix notation can be represented by changing the order of operations, but it is difficult to distinguish the expressions, and it is impossible to express priority in the case of the median notation, but the median notation It seems to have been written.
Parentheses are also used to indicate priorities in this median notation. The more such symbols, the more complex the equation will be.
So, how was the order of addition, division / multiplication and division decided?
In fact, it has been historically used to be defined as such.
Some argue that it is easier to calculate multiplication and division first, and that the equation is simpler.
A simple arithmetic operation in this way is actually a big thing even if the shape changes a little.
In Korea in 2005
111 + 1 x 2 = 224
There are cases like
Started in the United States in 2011 and shook the global online community
48 ÷ 2 (9 + 3) =?
There were also cases such as.
111 + 1 x 2 = 224
The correct answer is 113 according to the rule of arithmetic operation.
This has led to a myriad of masses of people who can not perform basic mathematical operations.
48 ÷ 2 (9 + 3) =?
In the case of the case, there was a lot of talk.
In order to solve this problem, we started with the rules of the American Mathematical Society, and there was an upsurge in the use of programming languages such as Mass-Meta and Python.
If we have learned the arithmetic operations so far, the correct answer will be 2, of course.
This is due to the multiplication by juxtaposition (MoJ) in the rule for the problem.
This rule is a rule that ab is denoted as a × b, and it is a convention to simplify the calculation. The answer depends on whether it is expressed in multiplication operation or other separate operation.
So this question has three answers.
When we look at MoJ as a new notation of ×: 288
When MoJ multiplies and divides and has higher priority than: 2
Principle As the principle is that it is impossible to omit the multiplication sign between numbers and numbers, the problem does not hold.
Arithmetic operation. It's a simple problem, but it can be difficult.