đề thi häc sinh giái nÌ lµm hộ mình với!

H

hiensau99

[TEX]\frac{2a+b+c+d}{a}= \frac{a+2b+c+d}{b}= \frac{a+b+2c+d}{c}= \frac{a+b+c+2d}{d}[/TEX]
\Rightarrow [TEX]\frac{2a+b+c+d}{a}-1= \frac{a+2b+c+d}{b}-1= \frac{a+b+2c+d}{c}-1= \frac{a+b+c+2d}{d}-1=\frac{a+b+c+d}{a}= \frac{a+b+c+d}{b}= \frac{a+b+c+d}{c}= \frac{a+b+c+d}{d}[/TEX]

+Nếu: [TEX] a+b+c+d \neq 0[/TEX] \Rightarrow[TEX]a=b=c=d[/TEX]. Khi đó: [TEX]M=1+1+1+1=4[/TEX]

+Nếu: [TEX] a+b+c+d=0[/TEX] \Rightarrow[TEX]a+b=-(c+d), b+c=-(d+a), c+d=-(a+b), d+a=-(b+c)[/TEX].khi đó: [TEX]M=-1-1-1-1=-4[/TEX]
 
Last edited by a moderator:
You must log in or register to reply here.
Top Bottom