hãy điền dấu +,- thích hợp
1...1...1...1...1...1...1...1...1...1=10
1...1...1...1...1...1...1...1...1...1=9
1...1...1...1...1...1...1...1...1...1=8
1...1...1...1...1...1...1...1...1...1=7
1...1...1...1...1...1...1...1...1...1=6
1...1...1...1...1...1...1...1...1...1=5
1...1...1...1...1...1...1...1...1...1=4
1...1...1...1...1...1...1...1...1...1=3
1...1...1...1...1...1...1...1...1...1=2
1...1...1...1...1...1...1...1...1...1=1
1...1...1...1...1...1...1...1...1...1=0