The sum of all such integers x thatsatisfy inequality 2≤丨2x-1丨≤6 is( )
问题描述：
The sum of all such integers x thatsatisfy inequality 2≤丨2x-1丨≤6 is( )
答
2≤丨2x-1丨≤6等价于：2≤丨2x-1丨且丨2x-1丨≤6(2x-1≤-2或2x-1≥2 ) 且 -6≤2x-1≤6(x≤-1/2或x≥3/2 )且 -5/2≤x≤7/2-5/2≤x≤-1/2或3/2x≤7/2由于x是整数,所以{ x |-2,-1,2,3 }所有元素的和为：-2-1+2+3=2 The...