Răspuns :
1) 2015 + 2x 2014 x 2015/2 = 2015 + 2014 x 2015 = 2015 x (1 + 2014) = 2015 x 2015 patrat perfect
2) x^2 + 3^4 = 15^2
x^2 = 225 - 81 = 144
x = 12
2) x^2 + 3^4 = 15^2
x^2 = 225 - 81 = 144
x = 12