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What are the zeroes of f(x) = x2 - X - 2?

x= -2,1
x = 2, -1
x= -2, -1
x = 2,1

User Ethan Post
by
2.4k points

2 Answers

18 votes
18 votes

Answer:

x=2, -1

Explanation:

Hi there!

We want to find the zeros of this function: f(x)=x²-x-2

The zeros are the values of x that will make f(x)=0

So that means in order to find the zeros, set f(x) as 0

In that case,

x²-x-2=0

Now let's solve the quadratic equation

We can do it by factoring

-x is the sum of two numbers, while -2 is the product of those two same numbers

Now think: which two numbers add up to -1, but multiply to get -2?

Those numbers are -2 and 1

Now factor the polynomial by FOIL:

(x-2)(x+1)=0

Split and solve

x-2=0

x=2

x+1=0

x=-1

The zeros are x=2, -1

Hope this helps!

User Techvice
by
2.9k points
17 votes
17 votes

Answer:

x=2 x=-1

Explanation:

f(x) = x^2 - X - 2

0= x^2 -x-2

Factor

0 =(x-2)(x+1)

Using the zero product property

x-2 =0 x+1 =0

x=2 x=-1

User Sokhom Ratanak
by
3.6k points