obliczyc P(A-B)

[oneone12]

Oblicz P(A-B), jezeli wiadomo ze P(B) = \(\displaystyle{ \frac{1}{3}}\), P=(\(\displaystyle{ A\cup B}\)) =\(\displaystyle{ \frac{2}{3}}\)

[bstq]

\(\displaystyle{ P\left(A\backslash B\right)=P\left(A\right)-P\left(A\cap B\right)=P\left(A\right)-\left(P(A)+P(B)-P\left(A\cup B\right)\right)=P\left(A\right)-P(A)-P(B)+P\left(A\cup B\right)=P\left(A\cup B\right)-P(B)}\)