Question

What are the zeros of the polynomial function: f(x) = (x - 3)(x + 1)(x - 5)?

Answer 1

When you write the polynomial in factored form like that, you can just read out the zeros, because they are the solutions to
factor1=0
factor2=0
factor3=0
etc.

so here
\[x-3=0\]\[x+1=0\]\[x-5=0\]

Answer 2

If you substitute any of the values you find by solving those trivial equations into the original polynomial, you'll see that the product is 0.