Question

Find the zeros of the function ƒ(x) = x2 + 2x – 3.

Answer 1

`f(x)=x^2+2x-3`

In order to determine the zeros of this function, the steps are:

1. Assume f(x) = 0. Hence, the equation becomes:

`0=x^2+2x-3`

2. Factor the quadratic function by finding some factors of -3 that sums to the middle term 2.

a. -3 and 1 → -2

b. -1 and 3 → 2

So, the factors of -3 that sums to 2 are -1 and 3.

So, the quadratic equation can be factored into:

`0=(x-1)(x+3)`

3. Equate each factor to zero and solve for x.

`\begin{gathered} x-1=0\Rightarrow x=1 \\ x+3=0\Rightarrow x=-3 \end{gathered}`

Therefore, the zeroes of the function are at (-3, 0) and (1, 0). (Option C)