Question

The set {-1, 0, 1} is not closed under which operation?

Answer 1

It's not closed under division, because \(1\div 0\) or \(-1 \div 0\) maps to \(\text{undefined}\).

Answer 2

If you try other operations, you'd map to an element present in the set.

Answer 3

\[0 \times 1 = 0 \\ 1 + (-1) = 0\\ -1 - 0 = -1 \\ \text{etc.} \]

Answer 4

@Riza Do you get it?

Answer 5

here is the things i can choose as an answer. multiplication, division, subtraction, all of the above

Answer 6

Just go through what I told you.

Answer 7

Closure property just states that you map to an element present in the set. Oh c'mon! You have done this in basic arithmetic too!

Answer 8

i think it multiplication

Answer 9

Why multiplication? Multiply any two numbers in the set, and you get a number that is present in the set.

Answer 10

\[1 \times 0 = 0 \]\[1 \times -1 = -1 \]\[-1 \times 0 = 0 \]

Answer 11

The set {0,1} is not closed under subtraction because we cannot subtract 1 from 0 in that set

Answer 12

lol, the question mentions the set {-1,0,1}.

Answer 13

bleh.

Answer 14

Ha ha ha..

Answer 15

Now I think you have left with only one option @Riza

Answer 16

its not multiplication division or subtraction

Answer 17

But you have guessed for Multiplication and Subtraction only..

Answer 18

\[-1 \div 1 = -1 \]\[-1 \div 0 = \text{underfined} \]Note how undefined is not given in the set.

Answer 19

Can you tell what is the value of:

\[\frac{1}{0} = ??\]