Question

Using the section of the graph shown, which of these potential roots of the function should you test first? f(x) = 2x3 – 9x2 – 6x + 40

Answer 1

-2

Explanation:

first point on the graph where the line hits x axis

Answer 2

Given the polynomial F(x)=2x3-9x2-6x+40, the first potential roots are -2, 4 and 5/2. Solving for the first root, we divide the given function by x+2 where the result is 2x2-13x+40. Since the given polynomial is divisible by x+2, therefore the first root is -2. For the second and third roots of the function, we can solve it using the quadratic equation formula.