(|3–m|/根号下1+m^2)=根号2怎么算?我算下是7/6可答案却是一个1一个–7

Question

(|3–m|/根号下1+m^2)=根号2 怎么算? 我算下是7/6 可答案却是一个1一个–7

Answer 1

楼主应该是算错了.|3–m|/√(1+m²)=√2|3–m|=√[2(1+m²)]|3–m|²={√[2(1+m²)]}²9-6m+m²=2(1+m²)m²+6m-7=0(m+7)(m-1)=0有：m+7=0、m-1=0解得：m1=-7、m2=1经检验,两根均为...