Question

-1又1/3×括号0.5-2/3括号除以一又1/9等于多少

不一有三分之一乘以括号零一五减三分之二括号除以又九分之一等于多少

Answer 1

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Answer 2

a2+b2 =(a-b)2+2ab =52+2×3 =25+6 =31 (a+b)2 =(a-b)2+4ab =52+4×3 =25+12 =37 a+b=±√(a+b)2=±√37 a2-b2=(a+b)(a-b)=±√37×5=±5√37