FunctionInjective

FunctionInjective[f,x] tests whether f(x)y has at most one solution x∈Reals for each y.

FunctionInjective[f,x,dom] tests whether f(x)y has at most one solution x∈dom. 

FunctionInjective[{f1,f2,…},{x1,x2,…},dom] tests whether f1(x1,x2,…)y1,f2(x1,x2,…)y2,… has at most one solution x1,x2,…∈dom.

FunctionInjective[{funs,xcons,ycons},xvars,yvars,dom] tests whether funs(xvars)yvars has at most one solution with xvars∈dom restricted by the constraints xcons for each yvars∈dom restricted by the constraints ycons. 

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