Find the zeros of f(x) = x^3 +9x^2 + 23x + 15

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f(x) = x^3 +9x^2 + 23x + 15

To solve, we will subsitute with the 15 factors which are:

1, -1, 3, -3, 5, -5, 15, -15

let us subsitute with x= -5:

f(-5) = 5^3 + 9*5^2 + 23*5 + 15

      = -125 + 225 - 529...

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f(x) = x^3 +9x^2 + 23x + 15

To solve, we will subsitute with the 15 factors which are:

1, -1, 3, -3, 5, -5, 15, -15

let us subsitute with x= -5:

f(-5) = 5^3 + 9*5^2 + 23*5 + 15

      = -125 + 225 - 529 + 15 = 0

The (x+5) is one of the factors:

==> f(x) = (x+ 5) * g(x)

Now we will divide f(x) by (x+5):

==> f(x) = (x+ 5) (x^2 + 4x + 3)

Now factor (x^2 + 4x + 3)

==> f(x) = (x+5)(x+3)(x+1)

Now we will determine the zeros:

==> x1= -5

==> x2= -3

==> x3= -1

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