Inequality Notation...2

Set 1.1





There is no inequality notation for
(-infinity, infinity). Why?

 

48. you did say x>sqrt(2) which means it is not included in solution, you need an empty circle at sqrt(2) (hole) like this


do same with 50 and 52

54. there is no hole at 0, 0 is part of solution

 

I will make all corrections later. Going out for a few hours.