(x-2)^2+(x-y+1)^2+(3x-y-5)^2的最小值

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(x-2)^2+(x-y+1)^2+(3x-y-5)^2的最小值(x-2)^2+(x-y+1)^2+(3x-y-5)^2的最小值(x-2)^2+(x-y+1)^2+(3x-y-5)^2的最小值利用a&

(x-2)^2+(x-y+1)^2+(3x-y-5)^2的最小值
(x-2)^2+(x-y+1)^2+(3x-y-5)^2的最小值

(x-2)^2+(x-y+1)^2+(3x-y-5)^2的最小值
利用a²+b²≥(a+b)²/2
(x-2)^2+(x-y+1)^2+(3x-y-5)^2
=(x-2)^2+(x-y+1)^2+(y-3x+5)^2
≥(x-2)^2+((x-y+1)+(y-3x+5))²/2…………( x-y+1=y-3x+5时取得等号)
=(x-2)^2+(-2x+6)²/2
=3x²-16x+22
=3(x-8/3)²+2/3
≥2/3 ……(x=8/3时取得等号)
将x=8/3代入x-y+1=y-3x+5得 y=10/3.

答案是1吗?
x=3,y=4.