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

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Answer 1 · 2016-02-27T17:57:57

$-1.236 or 3.236$

Use the quadratic formula to find points where $f(x)=0$ .

This occurs when $x=(-(-2)+-sqrt(2^2-4(1)(-4)))/((2)(1))$

$=(2+-sqrt20)/2$

$=-1.236 or 3.236$ .

We may verify this by plotting the graph of the function :

graph{x^2-2x-4 [-10, 10, -4.996, 5.005]}

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