Re: [中學] 97嘉中資優班考題

[JohnMash (Paul)]

※ 引述《qpzmm (欽仔)》之銘言：
: 化簡: [4^(1/3)-1]^1/2  + [16^(1/3)-4^(1/3)]^(1/2)

   a^3=4 and a>1

   a^4=4a

   a^2=2√a

   K=√(a-1) + √(a^2-a)

    =(√a + 1) √(a-1)

   K^2 =(√a + 1)^2 (a-1)

       =(a+1+2√a)*(a-1)

       =(a^2+a+1)(a-1)

       =a^3-1=3

   K=√3


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