What possible values of resultant resistance one can get by combining two resistances, one of value 2 ohm and the other 6 ohm?

R1 = 2 Ohm R2 = 6 Ohm

Let case 1 be parallel combination 1/R = 1/R1 + 1/R2

1/R = ½ + 1/6 = 4/6 R = 6/4 = 1.5 ohm

Let case 2 be series combination R = R1 + R2

= 2+6 = 8 ohm