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Solution - Finding the roots of polynomials

(2x32x2+2x1)(x+1)
(2x^3-2x^2+2x-1)*(x+1)

Step by Step Solution

Step  1  :

Multiplying exponential expressions :

 1.1    x1 multiplied by x3 = x(1 + 3) = x4

Equation at the end of step  1  :

  ((((x2) +  2x4) -  x2) +  x) -  1

Step  2  :

Polynomial Roots Calculator :

 2.1    Find roots (zeroes) of :       F(x) = 2x4+x-1
Polynomial Roots Calculator is a set of methods aimed at finding values of  x  for which   F(x)=0  

Rational Roots Test is one of the above mentioned tools. It would only find Rational Roots that is numbers  x  which can be expressed as the quotient of two integers

The Rational Root Theorem states that if a polynomial zeroes for a rational number  P/Q   then  P  is a factor of the Trailing Constant and  Q  is a factor of the Leading Coefficient

In this case, the Leading Coefficient is  2  and the Trailing Constant is  -1.

 
The factor(s) are:

of the Leading Coefficient :  1,2
 
of the Trailing Constant :  1

 
Let us test ....

  P  Q  P/Q  F(P/Q)   Divisor
     -1     1      -1.00      0.00    x+1 
     -1     2      -0.50      -1.38   
     1     1      1.00      2.00   
     1     2      0.50      -0.38   


The Factor Theorem states that if P/Q is root of a polynomial then this polynomial can be divided by q*x-p Note that q and p originate from P/Q reduced to its lowest terms

In our case this means that
   2x4+x-1 
can be divided with  x+1 

Polynomial Long Division :

 2.2    Polynomial Long Division
Dividing :  2x4+x-1 
                              ("Dividend")
By         :    x+1    ("Divisor")

dividend  2x4     + x - 1 
- divisor * 2x3   2x4 + 2x3       
remainder  - 2x3   + x - 1 
- divisor * -2x2   - 2x3 - 2x2     
remainder      2x2 + x - 1 
- divisor * 2x1       2x2 + 2x   
remainder      - x - 1 
- divisor * -x0       - x - 1 
remainder         0

Quotient :  2x3-2x2+2x-1  Remainder:  0 

Polynomial Roots Calculator :

 2.3    Find roots (zeroes) of :       F(x) = 2x3-2x2+2x-1

     See theory in step 2.1
In this case, the Leading Coefficient is  2  and the Trailing Constant is  -1.

 
The factor(s) are:

of the Leading Coefficient :  1,2
 
of the Trailing Constant :  1

 
Let us test ....

  P  Q  P/Q  F(P/Q)   Divisor
     -1     1      -1.00      -7.00   
     -1     2      -0.50      -2.75   
     1     1      1.00      1.00   
     1     2      0.50      -0.25   


Polynomial Roots Calculator found no rational roots

Final result :

  (2x3 - 2x2 + 2x - 1) • (x + 1)

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