Hello

Iv got an exam in a week and am trying to get through my whole course in that week. And am off to a horrible start =/

Can someone please tell how i should go about proving questions like the follwoing.

Q1)

A = {x <element_of> R | cos x = 1}

A = {x <element_of> R | sin x = 0}

Show that A <subsest of> B

Q2)

X = {24k + 7 | k <element_of> Z}

Y = {4n + 3 | n <element_of> Z}

Z= {6m + 1 | m <element_of> Z}

prove: X <subset_of> Y and X <subset_of> Z but Y <not_subset_of> Z

Thanks and im sure alot more questions would be comming soon =(