Question

Choose the correct vertex of the quadratic function f(x) = 3x2 - 2x - 1.

Answer 1

The vertex is (1/3, -4/3)

Answer 2

vertex is
`((-1)/(3), (-4)/(3))`

Explanation:

f(x) = 3x^2 - 2x - 1

Given equation is in the form of f(x) = ax^2 + bx+c

a=3 , b=-2 , c=-1

To find x coordinate of vertex we use formula x= -b/2a

`x=(-(-2))/(2(3)) = (-1)/(3)`

To find y coordinate of vertex plug in -1/3 in the place of x in f(X)

f(x) = 3x^2 - 2x - 1

`f((-1)/(3))= 3((-1)/(3))^2 -2((-1)/(3))-1= (-4)/(3)`

So vertex is
`((-1)/(3), (-4)/(3))`