Run hard@thehsc
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inequality proof question (1 Viewer)
- Thread starter Run hard@thehsc
- Start date
5uckerberg
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Do I have any like given statements for this question or do I have to prove the whole thing blindfolded.
this is better done multi-part given 
A) prove
B) prove(\frac{1}{a} + \frac{1}{b} + \frac{1}{c}) \geq 9 )
C) prove the above.
____________________________________________________________________________________________________________
A)^2 \geq 0)
divide everything by ab
B)(\frac{1}{a} + \frac{1}{b} + \frac{1}{c}))
 + (\frac{c}{a} + \frac{a}{c}) + (\frac{b}{c} + \frac{c}{b}) )
as required
C) let
using B:(\frac{1}{x+y} + \frac{1}{y+z} + \frac{1}{x+z}) \geq 9)
(\frac{1}{x+y} + \frac{1}{y+z} + \frac{1}{x+z}) \geq 9)
(\frac{1}{x+y} + \frac{1}{y+z} + \frac{1}{x+z}) \geq 9)
(\frac{1}{x+y} + \frac{1}{y+z} + \frac{1}{x+z}) \geq \frac{9}{2})
as required
A) prove
B) prove
C) prove the above.
____________________________________________________________________________________________________________
A)
divide everything by ab
B)
as required
C) let
using B:
as required
Last edited:
Run hard@thehsc
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Oh I was just given this question and it seemed weird! Thanks btw!