Question

How can. three resistance 2 ohm ,3 ohm, 6 ohm be connected to give a total resistance of 4r and -1 r

Answer 1

to give resistance of 4 ohm,
we will connect 3 ohm and 6 ohm resistance in parallel. and then connect resultant and 2 ohm resistance in series.
1/r=1/3 +1/6
=3/6=1/2
r=2 ohm
then, in series connection
R=2+2=4 ohm
And to get resultant be 1 ohm,
connect all resistance in parallel.
1/R= 1/2+ 1/3+ 1/6
=3+2+1/6
=1 ohm