Why does sgnx use SGN to represent symbolic function

Chinese translation of sign
Noun n. [C]
1. Mark, symbol
SGN is short for sign

RELATED INFORMATIONS

1. 45mm - how many decimeters is 15mm
2. What is the 63rd power of 2
3. 7 out of 8 times how much is 1, 5 out of 3 times how much is 1, 19 out of 18 times how much is 1
4. The maximum value x of function y = 2x / X & # 178; + 1 is greater than 0
5. What is composite number? What is prime number?
6. What is prime? What is composite? Let's make it clear. I've seen other people's stories, but I don't understand them
7. What are prime numbers and composite numbers Easy to understand
8. What are prime numbers and composite numbers
9. What compound numbers have prime numbers at the same time The least common multiple of these two numbers is 120. These two numbers are () and ()?
10. What is the meaning of prime number and composite number?
11. The ice at 0 ℃ melts into water at 0 ℃. Because the temperature remains the same, the internal energy remains the same
12. The image of function y = - xcosx Write the general process
13. Mother's English words
14. The first problem is to find the general solution of the differential equation y "+ y = 3x ^ 2. The second problem is to find the general solution of the differential equation y '- (Y-X) ^ 2 = 1 It's the Advanced Mathematics I learned in the University, but I forgot,
15. There are 40 English words (with Chinese meaning) beginning with H Must be 40, also have Chinese meaning. Time is urgent 40 40！
16. Calculate the square of 1949 - the square of 1950 + the square of 1951 - the square of 1952 + +The square of 1997 - the square of 1998 + the square of 1999
17. What an interesting job I do ( ) ( )( )I'm doing
18. Let f (x) be defined as R. if f (x + 1) and f (x-1) are both odd functions, then the function y = f (x) has at least one in the interval [0100]______ Zero
19. If students go boating, if each boat takes six people, two seats will be free; if each boat takes four people, three boats will be short. How many students go boating? How many boats did you hire?
20. Is the predicate after some vegetables plural or singular