Urgent!! Dau coroana!!

Răspuns:
x-1∈D14=> x-1∈{-1, 1, -2, 2, -7, 7, -14, 14}|+1 (adunam fiecare termen al multimii cu 1)
x∈{0, 2, -1, 3, -6, 8, -13, 15}
M= M3∩{0, 2, -1, 3, -6, 8, -13, 15}= {0, 3, -6, 15}