Question

Find the zeros of the function:

f(x) x^2-4x√5 +19

Answer 1

guess you can use the quadratic formula

Answer 2

it is really \[f(x)=x^2-4\sqrt{5}x+19\]?

Answer 3

It says \[f(x)=x^2-4x \sqrt{5}+19\]

Answer 4

same thing

Answer 5

use \[x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}\]with \[a=1, b=-4\sqrt5, c=19\]

Answer 6

I got \[\frac{ 4\sqrt{5}\pm2 }{ 2 }\]

Answer 7

Do I have to make it \[2\sqrt{5}\pm1\] instead?

Answer 8

Yes, good job!