The equivalent resistance of n resistors in parallel is given by
[tex] \frac{1}{R_{eq}}= \frac{1}{R_1}+ \frac{1}{R_2}+...+ \frac{1}{R_n} [/tex]
In this case, we have three resistors of [tex]6 \Omega[/tex] each, so their equivalent resistance when they are connected in parallel is
[tex] \frac{1}{R_{eq}}= \frac{1}{6 \Omega}+ \frac{1}{6 \Omega}+ \frac{1}{6 \Omega}= \frac{3}{6 \Omega} [/tex]
Which gives
[tex]R_{eq}= \frac{6 \Omega}{3}=2 \Omega [/tex]
