Question

Efectuati,folosind formula (a+b)²=a²+2ab+b².
a) (x+2)²; b) (a+4)²; c) (y+5)²; d) (2x+1)²

Answer 1

a) x² + 2·x·2 + 2² = x²+4x+4
b) a² +2·a·4 + 4² = a² + 8a + 16
c) y² + 2·y·5 + 5² = y² +10y + 25
d) (2x)² + 2·2x·1 + 1² = 4x² + 4x +1 ...Succes!!

Answer 2

a).   (x+2)²=x²+4x+4 ;
b).   (a+4)²=a²+8a+16 ;
c).   (y+5)²=y²+10y+25  ;
d).   (2x+1)²=4x²+4x+1 ;