Question

Find the additive inverse of each of the following: \[\dfrac{15}{-4}\] .

Answer 1

Hint: Problems like these are more often quite simple to understand and are easy to solve. We can solve such questions very quickly once we understand the underlying concepts behind the sum. To solve it, we need to have a fair amount of idea of number systems and invertible integers. In this particular question, we first of all need to get what the statement states. It says that, we need to find the additive inverse of a particular rational number, which means we need to find such a number, if possible, such that on adding this number with our given number in the problem, the result turns out to be zero.

Complete step by step solution:
Now we start off with the solution to the given problem by trying to figure out a number which when added to the given number results in a value equal to zero. Let the number be equal to ‘x’. The given number here is \[\dfrac{15}{-4}\] which is equal to \[-\dfrac{15}{4}\] . Now we add ‘x’ and this given number and equate it to zero. We then find the value of ‘x’.
\[\begin{align}
  & x-\dfrac{15}{4}=0 \\
 & \Rightarrow x=\dfrac{15}{4} \\
\end{align}\]

Thus our required answer to the problem is \[\dfrac{15}{4}\]

Note: To solve this problem, we need to have a thorough knowledge of number systems and invertible integers. We first of all need to figure out what number we should add so that the sum of the found out number and the given number becomes equal to zero. The simplest among all methods is just to reverse the sign of the number which is given in the problem. That will be our required answer.