(1)x=0, ax^5+bx^3+3x+c=c=-1
(2)x=1时,a+b+3+c=-1∴a+b+c=-4
(3)x=3时,a*3^5+b*3^3+3*3-1=-1,∴a*3^5+b*3^3+3*3=0
∴x=-3时,ax^5+bx^3+3x-1=a*(-3)^5+b*(-3)^3+3*(-3)-1=-[a*3^5+b*3^3+3*3]-1=0-1=-1
(4)(3)得,27a+3b=-1∵3a=5b∴a=-1/48, b=-1/80
∴a+b=(-5-3)/(16*3*5)=-1/30,c=-1
∴a+b>c
(1)、将x=0带入代数式得 c=-1.
(2)、将x=1带入代数式得 a+b+3+c=-1,得a+b+c=-4
(3)、由(1)得c=-1. 将x=3带入代数式得a*3^5+b*3^3+3*3-1=-1 得a*3^5+b*3^3=-9 得-a*3^5-b*3^3=9 将x=-3带入代数式得-a*3^5-b*3^3-9-1=9-9-1=-1
(4)、由(3)得a*3^5+b*3^3=-9 得 a*3^3+b*3=-1 又有3a=5b,得a=-5/144,b=-1/48 得a+b>c