a, Bội (6) = {0; 6}
b, Số đối của: -4 = 4 ; 0 = 0
c, \(3^2+10:2=9+10:2=9+5=14\)
Câu 2:
\(\left(15-\left[3^{20}:3^{19}+2022^0\right]\right):11=\left(15-\left[3^{20-19}+1\right]\right):11=\left(15-\left[3^1+1\right]\right):11\)
\(=\left(15-4\right):11=11:11=1\)
Câu 3:
\(2x-7=39\)
\(2x=39+7\)
\(2x=46\)
\(x=46:2\)
\(x=23\)