Question

How do you find the zeros of the function `f(x)= x^2-2x-4`?

Answer 1

The zeros of this function are `x_1=1-sqrt(5)` and `x_2=1+sqrt(5)`

To find the zeros of a quadratic function you first have to calculate `Delta`. In this case it is `Delta = (-2)^2-4*1*(-4) = 20`
`Delta > 0` so function has 2 real zeros which can be calculated using:

`x_1=(-b-sqrt(Delta))/(2a)` and `x_2 = (-b+sqrt(Delta))/(2a)`