Question

已知代数式ax^5+bx^3+3x+c,当x=3时,该代数式的值为-10,求当x=-3时该代数式的值!

Answer 1

设f(x)=ax^5+bx^3+3x+c,则f(3)=a*3^5+b*3^3+3*3+c= -10,故a*3^5+b*3^3+3*3= -10-c,故f(-3)=a*(-3)^5+b*(-3)^3+3*(-3)+c= -(a*3^5+b*3^3+3*3)+c=10+2c.