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# Proof Question watch

1. Hello it's me again, this time I have a problem with proof! I need to prove that for all positive values of x and y that: xy ≤ (x+y)/2.

I got to xy ≤ (x2+y2+2xy)/4 , but got stuck. Normally I would complete the square, but I don't know if this is possible with this algebra. Could I please get some help with this?
2. (Original post by Hughcifer)
Hello it's me again, this time I have a problem with proof! I need to prove that for all positive values of x and y that: xy ≤ (x+y)/2.

I got to xy ≤ (x2+y2+2xy)/4 , but got stuck. Normally I would complete the square, but I don't know if this is possible with this algebra. Could I please get some help with this?

What do we know about something squared?
3. (Original post by Hughcifer)
Hello it's me again, this time I have a problem with proof! I need to prove that for all positive values of x and y that: xy ≤ (x+y)/2.

I got to xy ≤ (x2+y2+2xy)/4 , but got stuck. Normally I would complete the square, but I don't know if this is possible with this algebra. Could I please get some help with this?

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