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Let

$X=AB-BA.$

We know that for any square matrices $A$ and $B$,

$\operatorname{tr}(AB)=\operatorname{tr}(BA).$

Therefore,

$\operatorname{tr}(X)=\operatorname{tr}(AB-BA)=\operatorname{tr}(AB)-\operatorname{tr}(BA)=0.$

Now let the eigenvalues of $X$ be $\lambda_1,\lambda_2,\lambda_3$.

Since $X$ is a $3 \times 3$ matrix, we have

$\lambda_1+\lambda_2+\lambda_3=\operatorname{tr}(X)=0.$

Also,

$\det(X)=\lambda_1\lambda_2\lambda_3$

and

$\operatorname{tr}(X^3)=\lambda_1^3+\lambda_2^3+\lambda_3^3.$

Using the identity

$a^3+b^3+c^3-3abc=(a+b+c)(a^2+b^2+c^2-ab-bc-ca),$

and putting $a=\lambda_1$, $b=\lambda_2$, $c=\lambda_3$, we get

$\lambda_1^3+\lambda_2^3+\lambda_3^3=3\lambda_1\lambda_2\lambda_3$

because

$\lambda_1+\lambda_2+\lambda_3=0.$

Hence,

$\operatorname{tr}(X^3)=3\det(X).$

So,

$\det(X)=\frac{\operatorname{tr}(X^3)}{3}.$

Since $X=AB-BA$, this gives
 

$\det(AB-BA)=\dfrac{\operatorname{tr}\left((AB-BA)^3\right)}{3}.$
 

Therefore the given statement is $\textbf{True}.$
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