Question

Sa se determine probabilitatea ca alegand un element din multimea A={sin 30, cos 30, tg 30, tg 45, tg 60} acesta sa fie numar rational.

Answer 1

$\it Elemente\ favorabile:\\ \\ sin30^o=\dfrac{1}{2} \in \mathbb{Q}\\ \\ tg45^o=1\in \mathbb{Q}\\ \\ p=\dfrac{nr.\ cazuri\ favorabile}{nr.\ cazuri\ posibile} \Rightarrow p=\dfrac{2}{5}$