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Probs not. It takes like 2-3 lines to prove, just do it this way;Also got a Q, am I allowed to just quote the AM >= GM inequality?
Yeah I picked up on that one hahahaOh and also making smart substitutions. Say you've just proved:
a^3 + b^3 + c^3 >= 3abc
Letting x= a^3 , y=b^3 , z= c^3 will lead you to the AM-GM result for n=3
And learning the neat little tricks as well! (algebra manipulation, substitution etc)Dw i'm in the same boat but these are some of the things I've picked up:
- Doing heaps of questions definitely does help. Not really actively memorizing things, but just learning how to recognize patterns.
- Most things start from any variation on (a-b)^2 >= 0 (i.e. change up the values of a and b for different q's)
- AM-GM is everything. You use it in like 80% of q's
- Always look at what they've asked you to just prove. You'll almost always use the result of pt i) in pt ii) or iii) or the result in ii) in iii)... you get the point
- While your proof has to be 'fowards' i.e. usually has to start from scratch, you can always work the question out backwards, get to an obviously true result, then reverse the process and cross out your initial working haha