Confusion with definition and notation of reciprocal.

Click For Summary
The discussion centers on the definition and notation of the multiplicative inverse, specifically how the reciprocal of a rational number a/b is defined as b/a. Participants clarify that the notation 1/x represents the operation of dividing 1 by x, rather than being a unique symbol. The relationship ab=1 is emphasized, indicating that if a is non-zero, b can be derived as 1/a through division. The conversation highlights that the confusion primarily lies in the interpretation of notation rather than the underlying mathematical concept. Ultimately, the distinction between notation and mathematical operations is key to understanding the reciprocal.
infranatural
Messages
2
Reaction score
0
Hello everyone,

I have some conceptual issues with aforementioned definitions.

How is exactly multiplicative inverse defined? Say, for a rational, nonzero number a/b, its reciprocal is b/a. Is there a certain operation that transforms a/b to b/a?

Also, the notation for multiplicative inverse of any real number (except zero) x is 1/x. Is 1/x a unique symbol or one that indicates operation of division of 1 by x?
For example, if x=2/3, should i see its inverse as 1/x=3/2, or as an operation of division, that is 1/x=1/(2/3)? I know that in the end the answer is the same, but what i'd like to know is if division is included in the "process" of obtaining that inverse or is it by definition that we just "flip" the numbers.
 
Mathematics news on Phys.org
Hey,

a^-b

(a "raised to" -b)

Or do you mean an alternative way to this too?
 
The Jericho said:
Hey,

a^-b

(a "raised to" -b)

Or do you mean an alternative way to this too?

No, no, a/b, a rational number, where a is some nonzero integer, and b is a natural number. No exponentiation here.
 
If a is any non-zero number then its reciprocal is defined as the number, b, such that ab= 1.

"Is 1/x a unique symbol or one that indicates operation of division of 1 by x?" Yes, it indicate division of 1 by x. If ab= 1, and a is not 0, we can divide both sides by a to get b= 1/a.

Your question seems to be more about notation than mathematics.
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 19 ·
Replies
19
Views
5K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 13 ·
Replies
13
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 23 ·
Replies
23
Views
2K
  • · Replies 41 ·
2
Replies
41
Views
5K