Please answer the attached question, thank you !!! 作者: 風之男 時間: 2021-1-7 05:10 PM
Well... what have you attempted so far?
At least in my opinion, this is not a "do your homework for you" forum, so please show some of your work or thought process, be it correct or not.
Anyhow, here are some hints:
(a) If you get stuck at proving identities, you can always try to prove "LHS-RHS=0" instead.
In the solution below, the method of completing square is used, but we're adding/subtracting the middle term instead of the usual last term.
If you've tried the "LHS-RHS=0" approach, you might get an idea why I chose to complete square
(or I've been factoring x^4+y^4 way too many times lately).