How do you find a polynomial function that has zeros #x=-3, 1, 5, 6# and degree n=5?

Question

1567 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2017-02-10T20:50:20

#=x^5-6x^4-22x^3+108x^2+189x-270#

The function could be the following:

#f(x)=(x+3)^2(x-1)(x-5)(x-6)#

that's

#=(x^2+6x+9)(x^2-6x+5)(x-6)#

#=(x^4cancel(-6x^3)+5x^2cancel(+6x^3)-36x^2+30x+9x^2-54x+45)(x-6)#

#=(x^4-22x^2-24x+45)(x-6)#

#=x^5-6x^4-22x^3+132x^2-24x^2+144x+45x-270#

#=x^5-6x^4-22x^3+108x^2+189x-270#