Question

How many real number solution does the equation x^3 + 5x^2 + 3x - 9= 0 have

Answer 1

3 real solutions.

Explanation:

Try x = 1 :

f(1) = 1 + 5 + 3 - 9 = 0

so x = 1 is a solution.

So x - 1 is a factor of the function.

If we divide the function by x - 1 we get the quotient x^2 + 6x + 9 which is

(x + 3)^2.

So there are 2 more roots of -3.