depinde de x din ce multime este
cazul a. x ∈ N x > 15 x∈ { 16, 17, 18 ,...........}
x > 11 x∈ { 11, 12, 13,......}
intersectam cele doua multimi , solutia finala x ∈ { 16, 17 ,........}
cazul b. x∈ R x >15 x∈( 15 , ∞)
x> 11 x∈( 11 , ∞)
x ∈ ( 15 ,∞ ) Π ( 11, ∞) = ( 15 , ∞ )
