dalianxiaozi8888
春芽
共回答了15个问题采纳率:86.7% 举报
1.原题应为 “若a+1/a=7,则根号a+1/根号a=?即√a+1/√a=?" ∵ (√a+1/√a) =a+2+1/a =2+(a+1/a) =2+7 =9.又√a≥0,1/√a>0 则√a+1/√a>0,∴√a+1/√a=√9=3.2.原题是这样吧:“定义运算 a 的运算法则为x a y=√(xy+4),则(2a6)a8=?” (2a6)a8 =[√(2*6+4)] a8 =[√16] a8 =4a8 =√(4*8+4) =√36 =6.
1年前
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