
 Integral 0 to PI/4 x*cos dx   
 
 based on open Newton-Cotes formulas    
 
 k=0   
 
    0.284948  
 
 k=1   
 
    0.277375  
 
 k=2   
 
    0.262297  
 
 k=3   
 
    0.262349  
 
 The exact value of intergation is :   
 
    0.262467  
 
 thus corresponding errors are :    
 
  - 0.022481  
  - 0.014907  
    0.000171  
    0.000118  
 
