In5C2ways=5!(5−2)!2!=5!3!2!=5×4×3!3!×2×1=10ways\begin{aligned} \text{In}\hspace{1mm}{}^{5}C_{2}\hspace{1mm}\text{ways}\hspace{1mm}= \frac{5!}{(5-2)!2!} \\ = \frac{5!}{3!2!} \\ = \frac{5\times4\times3!}{3!\times2\times1} \\ =10\hspace{1mm}\text{ways} \end{aligned}In5C2ways=(5−2)!2!5!=3!2!5!=3!×2×15×4×3!=10ways
