Inverse Operations
An English lesson - the word "inverse", which means the direct opposite. It is a most important concept.
Say we start with a number, ohh say 15.
Then we add 4. We now have 19.
Then we subtract 4. Now we have 15 again.
Therefore, adding and subtracting are the "direct opposite". That is to say they "un-do" each other.
Easy so far. Lets start with a different number, say 12.
Now, divide it by 6 and we have 2.
Now, multiply that by 6 and we have 12 again.
Therefore, multiplication and division are the "direct opposite". That is to say they "un-do" each other.
So, addition and subtraction are inverse operations.
And also multiplication and division are inverse operations.
Inverse operations are "direct opposites". They "un-do" each other.
One additional "inverse operation" is square root and square.
Pick a number. Lets assume you picked 12. Square it and you get 144.
Take the square root of 144 and you get the original 12. Square root and squaring
are "inverse operations".