Answer:
f(x) = 6x² - 24x + 21
Explanation:
The equation of a quadratic function in vertex form is
f(x) = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
Here (h, k ) = (2, - 3 ) , then
f(x) = a(x - 2)² - 3
To find a substitute (1, 3 ) into the equation
3 = 1(1 - 2)² - 3
3 = a(- 1)² - 3
3 = a - 3 ( add 3 to both sides )
6 = a
f(x) = 6(x - 2)² - 3 ← in vertex form
= 6(x² - 4x + 4) - 3
= 6x² - 24x + 24 - 3
f(x) = 6x² - 24x + 21 ← in standard form