设方程X^2+X-1=0的两个根是X1,X2.求4X1^5+10X2^3
方程X^2+X-1=0的两个根是X1,X2,所以,X1^2+X1-1=0,X1^2=1-X1,X2^2=1-X2,X1+X2=-1.
4X1^5=4X1^3（1-X1）=4X1^3-4X1^4=4X1^3-4X1^2(1-X1)=8X1^3-4X1^2
=……=20X1-12.
同样可得,10X2^3=20X2-10
所以,4X1^5+10X2^3=20X1-12+20X2-10=20（X1+X2）-22=-42.
（专解零回答,请把“红旗”插——最佳答案）
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