二次根式计算 ﹙√18﹚﹣﹙1/2﹚÷2﹣¹ +[1/﹙√2+1﹚] - [﹙√3﹚-1]º
问题描述:
二次根式计算 ﹙√18﹚﹣﹙1/2﹚÷2﹣¹ +[1/﹙√2+1﹚] - [﹙√3﹚-1]º
答
﹙√18﹚﹣﹙1/2﹚÷2﹣¹ +[1/﹙√2+1﹚] - [﹙√3﹚-1]º
=3√2-1/2÷1/2+√2-1-1
=4√2-3[1/﹙√2+1﹚]这里怎么处理1/(√2+1)=(√2-1)/(√2+1)(√2-1)=(√2-1)/(2-1)=√2-1