Question

La a scrie "scrieti sub forma de interval"
La b A inclus Z
La c A U {-1;1;2;3;5;7}
A={x €R| |x<5|

Answer 1

a)  |x| <5⇒ -5 < x < 5⇒ x∈(-5;5)⇒ A= (-5;5)
b)  A n Z = {-4,-3,-2,-1,0,1,2,3,4}
c)  A U {-1,1,2,3,5,7}= (-5:5] U {7}