How can three resistors of resistances 2 Ohms , 3 Ohms and 6 Ohms be connected to give total resistance of (i) 4Ohms (ii) 1Ohm
For total Resistance to be 4
we will connect 2 ohm resistance in series with parallel combination of 3 and 6 ohm resistance.
When 3 and 6 ohm are in parallel combination then 1/R=1/3+1/6= > R=2
Now this R connected in series with 2 ohm resistance will give equivalent resistance = 2+ 2 = 4 ohm.
For total Resistance to be 1 ohm
All the given resistance should be connected in parallel combination
1/R'=1/2+1/3+1/6 => R'=1 ohm