Solution 15 Solution : 1 + 1 – 1 = 1 1 x 1 + 1 = 1 + 1 x 1 = 2 1 + 1 + 1 = 3 (1 + 1)2 x 1 = 4 (1 + 1)2 + 1 = 5 (1 + 1 + 1) ! = 6 ((1 + 1)3 ) – 1 = 7 ((1 + 1)3 ) x 1 = 8 (1 + 1 + 1)2 = ((1 + 1)3 ) + 1 = 9
