To maximize profit, what condition must be met regarding Marginal Cost (MC) and Marginal Revenue (MR)?

Profit is maximized at the output level where the additional revenue from selling one more unit (MR) equals the additional cost of producing that unit (MC).Mathematically, $P(x)=R(x)-C(x)$. To maximize, $P^{\prime }(x)=R^{\prime }(x)-C^{\prime }(x)=0⟹MR-MC=0⟹MR=MC$.