Question

Efetue o quadrado da soma de dois termos:
a)(x+y)²
b)(5a+2b)²
c)(x²+¹/²x)²

Answer 1

a) 
(x+y)² = (x+y).(x+y) = x² + xy + xy + y² = x² + 2xy + y²
b)
(5a+2b)² = (5a)² + 2.(5a).(2b) + (2b)² = 25a² + 20ab + 4b²
c)
(x²+(x/2))² = (x²)² + 2.x².x/2 + (x/2)² = x^4 + x³ + x²/4

Answer 2

letra A (x + y)² = x² + 2xy + y²              = x² + y² + 2xy = 25 + 2.12 = 25 + 24 = 49