Find a cubic polynomial function having the graph shown Solu
Find a cubic polynomial function having the graph shown.
Solution
95 ) graph cuts the x axis at x= -5
zero at x=-5
graph touches the x axis at x = 3
zero at x=3 of multiplicity 2
Polynomial: f(x) = k(x+5)(x -3)^2
We would the constant k by using point (0, 9)
9 = k(5)(-3)^2
k= 1/5
f(x) = (1/5)(x+5)(x -3)^2
f(x) = (x+5)(x^2 +9 -6x)/5
= (x^3 +9x -6x^2 +5x^2 +45 -30x)/5
=(x^3 -x^2 -21x +45)/5
