Réponses

2013-05-01T22:04:27+02:00

1)

 

f(x) = 3(x+2)²-27

= 3(x²+4x+4)-27

= 3x²+4x+12-27

=3x²+4x-15

 

f(x) = 3(x-1)(x+5)

=3(x²+4x-5)

=3x²+12x-15

 

2) 

 

3(x-1)(+5)=0

x-1=0 ou x+5=0

x=1          x=-5