函数y=x²+2/x-1(x>1)的最小值是答案是2根号3+2求解

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函数y=x²+2/x-1(x>1)的最小值是
答案是2根号3+2求解


y=x^2+2/x-1
=[(x-1)^2+2x+1]/(x-1)
=[(x-1)^2+2(x-1)+3]/(x-1)
=(x-1)+3/(x-1)+2
≥2√(x-1)×3/(x-1) +2
=2√3 +2