Question

Solve (x + 2 < 5) ∩ (x - 7 > -6).



{x | 1 < x < 3}
{x | x < 3 or x > 1}
{all real numbers}

Answer 1

it's not x<3 or x>1 but x<3 AND x>1 (First answer) why? the intersection means that you use "the repeated" data.
So it will be (x+2<5=>x<3) (x-7>-6=>x>1) -> so its x ∈ (1,3) (The interval is open in both extremes)