Name: Natalia
Who is asking: Student
Level: Secondary

Question:
Hello!
How can I solve:
2 x3 - x2 + x - 2 = 0 ???

Hi Natalia,
For polynomial equations of degree higher than 2 the first thing to do is to look for some grouping of terms that will result in a common factor. For your equation

2 x3 - x2 + x - 2 = 0

I put the two terms with coefficient 2 together to get

2 x3 - 2 - x2 + x = 2(x3 - 1) - x(x - 1) = 0

Now factor x3 - 1 and simplify.
   Another way to approach this problem is with the Factor Theorem. With

p(x) = 2 x3 - x2 + x - 2

it is easy to see that p(1) = 0 so (x - 1) is a factor of p(x). The second factor can be found by division.

Cheers,
Penny

 

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