# Thread: Cardinal numbers - help prove basic properties

1. ## Cardinal numbers - help prove basic properties

Hey all, I need help with the following questions:

1) prove that t+aleph0 = aleph0 for any t finite number.
2) t*aleph0 = aleph0 for any t finite number
3) t+aleph1 = aleph1 for any t finite number

2. ## Re: Cardinal numbers - help prove basic properties

Originally Posted by OriaG
Hey all, I need help with the following questions:
1) prove that t+aleph0 = aleph0 for any t finite number.
2) t*aleph0 = aleph0 for any t finite number
3) t+aleph1 = aleph1 for any t finite number

Oh, come on!
What is the definition of $t+\aleph_0~?$

How do you define equality for $t+\aleph_0=\aleph_0~?$.

Answer those questions and show some work.