Răspuns :
Răspuns:
a).(x+y)^2= x^2+ 2xy+ y^2
b).(x+2)^2= x^2 + 2*2*x + 2^2 = x^2+ 4x +4
c).x^2-1= x^2 -2+ 1
d). (3x+1)^2=3^2*x^2+ 2*3*x+ 1^2= 9x^2+ 6x+ 1
e). (x-y)^2= x^2-2xy + y^2
Răspuns:
a).(x+y)^2= x^2+ 2xy+ y^2
b).(x+2)^2= x^2 + 2*2*x + 2^2 = x^2+ 4x +4
c).x^2-1= x^2 -2+ 1
d). (3x+1)^2=3^2*x^2+ 2*3*x+ 1^2= 9x^2+ 6x+ 1
e). (x-y)^2= x^2-2xy + y^2