Pre-Calc B

posted by .

How do I find zeros on a graph of a cubic function? I can tell that two of the zeros are -4 and 3 because they show on the graph, but how do I find the other?

  • Pre-Calc B -

    y = a x ^ 3 + b x ^ 2 + c x + d = a ( x - x1 ) ( x - x2 ) ( x - x3)

    y = a [ x - ( - 4 ) ] ( x - 3 ) ( x - x3 )


    y = a ( x + 4 ) ( x - 3 ) ( x - x3 )

    You must know 4 points on graph to solve this equation.

    Maybe your function has a double root (that is, one of the zeroes has a multiplicity of two).

    In this case :

    y = a ( x + 4 ) ( x + 4 ) ( x - 3 )

    OR

    y = a ( x + 4 ) ( x - 3 ) ( x - 3 )

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. pre cal

    Given f(x)=x^4-7x^3+18x^2-22x+12 A: list all possible rational zeros B: Graph f(x) C: Find all zeros D: show f(x) in factured form thanks I can't figure it out. Can skip B... thanks
  2. Pre Calc

    7. The Sandusky Little League uses a baseball throwing machine to help train 10-year old players to catch high pop-ups. It throws the baseball straight up with an initial velocity of 48 ft/sec from a height of 3.5 ft. a. Find an equation …
  3. calculous

    3.Given the function f defined by f(x)=2x^3-3x^2-12x+20 a.Find the zeros of f b.Write an equation of the line perpendicular to the graph of f at x = 0 c. Find the x and y coordinates of all points on the graph of f where the line tangent …
  4. pre cal

    g(x) = x^2 - x -12 / x + 1 I know the division brings it to x -2 + -10/x + 1 but these are the steps I have to follow 1. factor the numerator and denominator and find its domain. ( I know 0 is not in domain) 2. write in lowest ermas …
  5. Math Problem (please help)

    Find all the zeros of the function. When there is an extended list of possible rational zeros, use a graphing utility to graph the function in order to discard any rational zeros that are obviously not zeros of the function. (Enter …
  6. Pre-Calc

    Find the zeros of the function algebraically. Show all work. f(x)=x^2-8x+15 ---------------- 10x
  7. Pre-Calc

    Find the zeros of the function algebraically. Show all work. f(x)=x^2-8x+15 ---------------- 10x
  8. Math

    I just wanted to double check that I am correct. 1.Find the zeros for the function: f(x)= 4(x-3)(x+2)(x-4)^2 Zeros are: 3,-2, 4(multiplicity 2) 2.Find the zeros for the function: f(x)= x^3-9x Zeros are: 0, 3, -3
  9. Algebra 2!!!!

    Use the graph to shorten the list of possible rational zeros of the function. Then find all real zeros of the function. 1.) f(x)= 4x^3-8x^2-15x+9 4.) f(x)= 2x^3-5x^2-4x+10
  10. Pre-Calculus

    For the function f(x)=12x^3+4x^2-27x-9 describe the end behavior. Find the real zeros of f and determine whether the graph crosses or touches the x-axis at each x-intercept. Use the zeros of f and test numbers to find the intervals …

More Similar Questions