NMaxValue

NMaxValue[f,x] gives the global maximum value of f with respect to x.

NMaxValue[f,{x,y,…}] gives the global maximum value of f with respect to x, y, …. 

NMaxValue[{f,cons},{x,y,…}] gives the global maximum value of f subject to the constraints cons. 

NMaxValue[…,x∈reg] constrains x to be in the region reg.

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