早教吧 育儿知识 作业答案 考试题库 百科 知识分享

三个不等于零的有理数a,b,c满足(a+b)(b+c)(c+a)=0,则(a+b+c)(a3+b3+c3)(a5+b5+c5)(a7+b7+c7)(a9+b9+c9)a25+b25+c25=.

题目详情
三个不等于零的有理数a,b,c满足(a+b)(b+c)(c+a)=0,则
(a+b+c)(a3+b3+c3)(a5+b5+c5)(a7+b7+c7)(a9+b9+c9)
a25+b25+c25
=___.
▼优质解答
答案和解析
∵三个不等于零的有理数a,b,c满足(a+b)(b+c)(c+a)=0,∴a+b=0或b+c=0或c+a=0,∴a=-b或b=-c或c=-a,
当a=-b时,a+b+b=-b+b+c=c,
a3+b3+c3=(-b)3+b3+c3=-b3+b3+c3=c3
a5+b5+c5=(-b)5+b5+c5=-b5+b5+c5=c5
a9+b9+c9=(-b)9+b9+c9=-b9+b9+c9=c9
a25+b25+c25=(-b)25+b25+c25=-b25+b25+c25=c25
(a+b+c)(a3+b3+c3)(a5+b5+c5)(a7+b7+c7)(a9+b9+c9)
a25+b25+c25
=
c×c3×c5×c7×c9
c25
=
c1+3+5+7+9
c25
=
c25
c25
=1,
同理:当b=-c时或当c=-a时,则
(a+b+c)(a3+b3+c3)(a5+b5+c5)(a7+b7+c7)(a9+b9+c9)
a25+b25+c25
=1,
即:则
(a+b+c)(a3+b3+c3)(a5+b5+c5)(a7+b7+c7)(a9+b9+c9)
a25+b25+c25
=1,
故答案为1.