16 find all the zeroes of the polynomial x4 x3 − 34x2 − 4x 120 if two of its zeroes are 2 and 2

Verify that the numbers given alongside of the cubic polynomials below are their zeroes. Also, verify the relationship between the zeroes and coefficients in each case:
2x3 + x2 –5x + 2; 1/2, 1,–2 

Let p(x) = 2x3+x2–5x + 2 Comparing the given polynomial with ax3 + bx3 

+ cx + d, we get
                    

Now, 
                     
                           

                          

          
                    
and   
                  
∴    are the zeroes of 
Hence, verified.Here, we have

Now,    
         
                            
and           
                                   Hence verified.