Question

find roots for y=x³-3x+3​

Answer 1

Answer:

x

3

−3x−2=0

Clearly x=−1 is a solution of the equation, hence (x+1) is a factor of the equation

x

2

−x−2

_______________

x+1)x

3

−3x−2

x

3

+x

2

__________________

−3x−2−x

2

−x −x

2

___________________

−2x−2

−2x−2

____________

0

____________

⇒x

2

−x−2

⇒x

2

+2x−x−2=0

⇒x(x+2)−1(x+2)=0

⇒(x−1)(x+2)=0

Factors ⇒(x+1)(x−1)(x+2)=0

Roots ⇒−1,1,−2.