The Exercise Correction 4 natural integers numbers




1) 
a= x²-5x+4=x²- 2 x +1- 3 x +3 =(x - 1 )² - 3 (x- 1)

=(x - 1 )(x - 1 - 3 )=(x - 1 )(x - 4 )

b =2x²+3x-2 =2x²+4x- x -2 =2x  (x +2 )-(x +2 )
=(x +2 )(2 x - 1 ) 

2) 







3) 

4) the product of two consecutive integers is a natural even number