Question

Exercițiul 1 si 2 dau coroana si 30 puncte

Answer 1

1. a) (x+y)^2 = x^2 + 2xy + y^2

b) (a-3)^2 = a^2 - 2a×3 + 3^2 = a^2-6a+9

c) (x+a)^2 = x^2 + 2ax + a^2

d) (b-a)^2 = b^2 -2ab + a^2 

e) (3-x)^2 = 3^2 - 2×3×x + x^2 = x^2-6x+9

f) ( 4+a)^2= a^2 + 8a + 16


2. a) (2x-3y)^2 = (2x)^2 -2×2x×3x +(3y)^2

b) ( 3a+5b)^2 = 9a^2 + 30ab + 25b^2

c) ( rad 3x - rad 2y )^2 = 3x - 2 rad 6xy + 2y

d) (1/3a+2x)^2 = 1/9a^2 +4/3ax +4x^2

e) ( rad 3 + 3b )^2 = 3 + 6 rad 3b +9b^2

f) (b/4 - a/3)^2 = b^2/16 - ab/6 + a^2/9