For the polynomial, list each real zero and its multiplicity. Determine whether
ID: 2963500 • Letter: F
Question
For the polynomial, list each real zero and its multiplicity. Determine whether the graph crosses or touches the x-axis at each x -intercept.
f(x) = x(x2 - 5)
1. (sqrt{5}, multiplicity 1, touches x-axis; -sqrt{5}, multiplicity 1, touches x-axis)
2. 0, multiplicity 1
3. 0, multiplicity 1, touches x-axis; (sqrt{5}, multiplicity 1, touches x-axis; -sqrt{5}, multiplicity 1, touches x-axis)
4. 0, multiplicity 1, crosses x-axis; (sqrt{5}, multiplicity 1, crosses x-axis; -sqrt{5}, multiplicity 1, crosses x-axis)
Explanation / Answer
f(x) =x(x^2-5)
x =0 multiplicity of 1, crosses the x axis
x^2=5
x = sqrt 5 multiplicity of 1, crosses the x axis
x = -sqrt 5 multiplicity of 1, crosses the x axis
therefore answer is 4