E così?
Però mi è saltato il margine che rientravo a sx con \hspace{-30pt} 😯
Se solo riuscissi a trovare il modo per restringere quei maledetti esponent!
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\hspace{-30pt}
\begin{tabular}{*{1}{>{$}c<{$}}*{1}{>{\columncolor[RGB]{215,215,215}$}c<{$}}*{1}{>{$}c<{$}}*{1}{>{\columncolor[RGB]{215,215,215}$}c<{$}}*{1}{>{$}c<{$}}} \toprule & \Delta CU & \Delta D & \Delta R & \Delta CR \\ \midrule 1 & \frac{CU}{M} }\Delta H & \frac{D}{M}\Delta H & \theta\frac{D}{M}\Delta H & \left( {1 - \theta} \right)\frac{D}{M}\Delta H \\ 2 & \left( {1 - \theta} \right)\frac{D}{M}\frac{CU}{M}\Delta H & \left( {1 - \theta} \right)\left( {\frac{D}{M}} \right)^2 \Delta H & \theta\left( {1 - \theta} \right)\left( {\frac{D}{M}} \right)^2 \Delta H & \left( {1 - \theta} \right)^2 \left( {\frac{D}{M}} \right)^2 \Delta H \\ 3 & \left( {1 - \theta} \right)^2 \left( {\frac{D}{M}} \right)^2 \frac{CU}{M}\Delta H & \left( {1 - \theta} \right)^2 \left( {\frac{D}{M}} \right)^3 \Delta H & \theta\left( {1 - \theta} \right)^2 \left( {\frac{D}{M}} \right)^3 \Delta H & \left( {1 - \theta} \right)^3 \left( {\frac{D}{M}} \right)^3 \Delta H \\ 4 & ... & ... & ... & ... \\ n & \left( {1 - \theta} \right)^{n-1} \left( {\frac{D}{M}} \right)^{n-1} \frac{CU}{M}\Delta H & \left( {1 - \theta} \right)^{n-1} \left( {\frac{D}{M}} \right)^n \Delta H & \theta\left( {1 - \theta} \right)^{n-1} \left( {\frac{D}{M}} \right)^n \Delta H & \left( {1 - \theta} \right)^n \left( {\frac{D}{M}} \right)^n \Delta H \\ \bottomrule \end{tabular}