Given, \(P(X = a) = r\)
\[
P\Bigg(max(X,Y)=a\Bigg)=P(X =a,Y ≤a)+P(X ≤a,Y =a)−P(X =a,Y =a)
\]
\[
P\Bigg(min(X,Y)=a\Bigg)=P(X =a,Y >a)+P(X >a,Y =a)+P(X =a,Y =a).
\]
Thus,
\[ => P\Bigg(max(X,Y) = a)+P(min(X,Y) = a\Bigg) = P(X = a)+P(Y = a) \]
and so,
\[ => u = t+s−r \]