A binary operation ⊗ defined on the set of integers is such that m⊗n = m + n + mn for all integers m and n. Find the inverse of -5 under this operation, if ...
A binary operation ⊗ defined on the set of integers is such that m⊗n = m + n + mn for all integers m and n. Find the inverse of -5 under this operation, if the identity element is 0
Answer Details
To find the inverse of -5 under this operation, we need to find an integer x such that -5⊗x = 0, where 0 is the identity element.
Using the given binary operation, we know that m⊗n = m + n + mn. Substituting -5 for m and x for n, we get:
-5⊗x = -5 + x - 5x = -4x - 5
We need to solve -4x - 5 = 0 for x. Adding 5 to both sides gives:
-4x = 5
Dividing both sides by -4 gives:
x = -5/4
Therefore, the inverse of -5 under this operation is -5/4.
So, the correct option is: -5/4