2007-12-17 05:12:23 · 4 answers · asked by lilmars114@sbcglobal.net 1 in Science & Mathematics ➔ Mathematics
f(1) = 1 - 3 - 1 + 3
f(1) = 0
Thus x - 1 is a factor of f(x)
Find other factors by using synthetic division:-
1| 1 __- 3____- 1_____3
"|_____1_____- 2____- 3
"| 1___- 2____- 3_____0
(x - 1)(x² - 2x - 3) = 0
(x - 1)(x - 3)(x + 1) = 0
x = - 1 , x = 1 , x = 3
2007-12-21 03:32:23 · answer #1 · answered by Como 7 · 0⤊ 1⤋
X^3-3x^2-x+3=0
==>x^2(x-3)-1(x-3)=0
==>(x^2-1)(x-3)=0
==>(x+1)(x-1)(x-3)=0
==>x = -1,1,3
2007-12-17 13:22:19 · answer #2 · answered by heyerfan 2 · 2⤊ 0⤋
HINT:
x = 1 is one solution (trick: if the coefficients add together to be 0, then x = 1, is always a solution to the polynomial expression).
To get the other two roots: Use long division and divide the cubic equation by x-1. The quotient will be a quadratic expression. Then you set that equal to zero and solve the quadratic equation to find the other two roots.
2007-12-17 13:20:54 · answer #3 · answered by KG06 3 · 0⤊ 0⤋
x=-1,1,3
2007-12-17 13:17:26 · answer #4 · answered by Anonymous · 0⤊ 0⤋