Yang bagian A doank ya

Diketahui :
A = {1,2,3,4,5,6,7}
B = {-3,-2,-1,0,1,2,3,4}
C = {0,1,2,3,4,5,6,7,8}

Ditanya :
A U B U C ?

Jawab :
A U B U C = {-3,-2,-1,0,1,2,3,4,5,6,7,8}


semoga membantu =)