Show that [properties] can be deduced as a theorems, Spivak

[usn7564]

Homework Statement

http://desmond.imageshack.us/Himg228/scaled.php?server=228&filename=theorem.png&res=landing

Picked up Spivak's Calculus, 3rd ed. and just started. Got to this question and I'm honestly not sure how to start, I looked in the answer book which didn't really clue me in any more.
If I understand the question it wants me to work within the four properties and show that there is no contradiction/they all have to apply? Not a native English speaker so I haven't had maths in English but that's what I got from it.

More interested in how to approach it rather than answers, would assume there's coming a lot more similar questions. Not really done any proof based maths up until now.

 

[Infinitum]

Homework Statement

http://desmond.imageshack.us/Himg228/scaled.php?server=228&filename=theorem.png&res=landing

Picked up Spivak's Calculus, 3rd ed. and just started. Got to this question and I'm honestly not sure how to start, I looked in the answer book which didn't really clue me in any more.
If I understand the question it wants me to work within the four properties and show that there is no contradiction/they all have to apply? Not a native English speaker so I haven't had maths in English but that's what I got from it.

More interested in how to approach it rather than answers, would assume there's coming a lot more similar questions. Not really done any proof based maths up until now.

P10-P12 are properties given in the book previously(which you haven't included). You need to prove those properties using the given new ones.

 

[usn7564]

Ah, Christ, no wonder I didn't get it even with the answers in front of me. Know what direction I'm heading now at least, ta.