Answer:
Example: <em>- 2x³ + 10x²</em>
Step-by-step explanation:
1.<em>A cubic function</em> is a polynomial of degree 3 in one variable. This means that the highest exponent of the variable is 3: <em>x³</em>
2. <em>Leading coefficient</em> is the coefficient of the term with the highest exponent: in <em>ax³</em> <em>the leading coefficient is a</em>.
3. General form of a <em>cubic function</em>: ax³ + bx² + cx + d, where a ≠ 0
4. <em>Zeros</em> of a polynomial function are the values of x for which the polynomial values zero: <em>ax³ + bx² + cx + d = 0</em>
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5. When the polinomial is factored you can tell easily which the zeros are.
This is how a factored cubic function looks: a(x - x₁)(x - x₂)(x - x₃), where <em>a is the leading coefficient, and x₁, x₂, and x₃ are the three zeroes of the function</em>.
With that, you can write a cubic function with the restrictions stated:
- l<em>eading coefficien of - 2</em>: a = - 2
- <em>one positive zero</em>: x₁ = 5
- for facility, make the other zeros equal to zero, x₂ = 0, and x₃ = 0
- name the function f(x)
result: f(x) = - 2( x -5)(x - 0)(x -0) = -2(x - 5)(x)(x)
- Expand the expression using distributive property:
- 2x³ + 10x²