Solve infinitesimal questions on Wolfram|Alpha?

Hi there,
I am trying to solve the question (0,3)[1,2]
but Wolfram gives me the wrong answer
the right answer must be >> (0,3) or (1,2)!!
How I can type infinitesimal questions on Wolfram?

I am trying to solve also this question with WolframAlpha how can I do this>>


For each of the groups, determine whether it is blocked from above and blocked from above:
I am trying to find the

–A=(1,2)∪(5,6)

–A={n-n^2 |n∈N}

–A=Z∩(-100.5,∞)