Evaluate (i) {(13)−1−(14)−1}−1 (ii) (58)−7×(85)−4
(i) {(13)−1−(14)−1}−1
={(31)1−(41)1}−1 [∵(ab)−m=(ba)m]
={3−4}−1=(−1)−1=1−1=−1
(ii) (58)−7×(85)−4
=(5−78−7)×(8−45−4) [∵{ab}m=ambm]
=8757×5484 [∵a−m=1am]
=87−457−4 [∵am÷an=am−n]
=8353=512125
Evaluate (i) (ii)