Question

Which of the following is not the additive inverse of $a$?

• A. $-\left(-a\right)$
• B. $a\times \left(-1\right)$
• C. $-a$
• D. $a÷\left(-1\right)$

Answer 1

The correct option is A

$-\left(-a\right)$

Explanation.

Additive inverse : An additive inverse is a number when adding it to the given number yields zero.

The additive inverse of $a$ is $-a$ as, $a+\left(-a\right)=0$

Now,

$$\begin{gathered} -\left(-a\right)=a \\ a\times \left(-1\right)=-a \\ a÷\left(-1\right)=-a \end{gathered}$$

Thus, additive inverse of $a$ is not $a$.

Hence, the correct option is $\mathrm{A}$.