Question

(2x +1) (x +3) ( x -1) = 0

Answer 1

Ola Marina 

(2x + 1)*(x + 3)*(x - 1) = 0

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2x + 1 = 0
2x = -1
x = -1/2

x + 3 = 0
x = -3

x - 1 = 0
x = 1

S = (-3, -1/2, 1)