急!!求过程and答案(写纸上)急!!
3个回答
展开全部
抱歉,由于特殊原因,只能打(真得很抱歉)
(7)原式=(1/3x)*√(27x)+(1/3x)*√[3x(x+3)²]+(1/3x)*√[3x(x-3)²]
=(1/3x)*[3√3x+(x+3)√(3x)+(3-x)√(3x)
=(1/3x)*[9√(3x)]
=[9√(3x)]/3x
=[3√(3x)]/x
(8)原式=[(√2+3√3-2√5)(√2-√3)(√3+√5)] / [(√2-√3)(√3+√5)(√2+√3)(√3-√5)]
=(9√5-4√2-7√3)/2
十分抱歉,只能做到这样了
(7)原式=(1/3x)*√(27x)+(1/3x)*√[3x(x+3)²]+(1/3x)*√[3x(x-3)²]
=(1/3x)*[3√3x+(x+3)√(3x)+(3-x)√(3x)
=(1/3x)*[9√(3x)]
=[9√(3x)]/3x
=[3√(3x)]/x
(8)原式=[(√2+3√3-2√5)(√2-√3)(√3+√5)] / [(√2-√3)(√3+√5)(√2+√3)(√3-√5)]
=(9√5-4√2-7√3)/2
十分抱歉,只能做到这样了
展开全部
第一题第一个回答者的是正确的,第二题思路也对,但结果出现了差错,我给你解第2题吧。
(√2+3√3-2√5)/[(√2+√3)(√3-√5)]
=[(√2+√3)+2(√3-√5)](√3-√2)(√3+√5)] / [(√3-√2)(√3+√5)(√2+√3)(√3-√5)]
=[(√2+√3)(√3-√2)(√3+√5)+2(√3-√5)(√3+√5)(√3-√2)(√3+√5] / [(√3²-√2²)(√3²-√5²)]
=[(√3²-√2²)(√3+√5)-2(√3²-√5²)(√3-√2)]/(-2)
=[(√3+√5)+(-4)(√3-√2)] / (-2)
=(√5-3√3+4√2)/ (-2)
(√2+3√3-2√5)/[(√2+√3)(√3-√5)]
=[(√2+√3)+2(√3-√5)](√3-√2)(√3+√5)] / [(√3-√2)(√3+√5)(√2+√3)(√3-√5)]
=[(√2+√3)(√3-√2)(√3+√5)+2(√3-√5)(√3+√5)(√3-√2)(√3+√5] / [(√3²-√2²)(√3²-√5²)]
=[(√3²-√2²)(√3+√5)-2(√3²-√5²)(√3-√2)]/(-2)
=[(√3+√5)+(-4)(√3-√2)] / (-2)
=(√5-3√3+4√2)/ (-2)
已赞过
已踩过<
评论
收起
你对这个回答的评价是?
推荐律师服务:
若未解决您的问题,请您详细描述您的问题,通过百度律临进行免费专业咨询