Question

(х-3) : x^2-6x+9/x+3 при х=-21

Answer 1

(х-3) : ((x²-6x+9)/(x+3)) =  (х-3) : ((x-3)²/(x+3))  =  (х-3) * ((x+3)/(x-3)²)  =

=  (х+3)/(x-3)    

 при х= - 21   (21+3)/( 21-3)  = 24/18 = 4 /3 = 1. 1/3