Question

Questão 5. Determine:
a) (7 + x)2
b) (y - 3)2
c) (x2 + x)2
d) (x - 3y)2
e) (2x + 3)2
(Aulas 13 a 20)
Correção das atividades.​

Answer 1

Oie, Td Bom?!

a)

$= (7 + x) {}^{2}$

$= 7 {}^{2} + 2 \: . \: 7x + x {}^{2}$

$= 49 + 14x + x {}^{2}$

$= x {}^{2} + 14x + 49$

b)

$= (y - 3) {}^{2}$

$= y {}^{2} - 2y \: . \: 3 + 3 {}^{2}$

$= y {}^{2} - 6y + 9$

c)

$= (x {}^{2} + x) {}^{2}$

$= (x {}^{2} ) {}^{2} + 2x {}^{2} \: . \: x + x {}^{2}$

$= x {}^{4} + 2x {}^{3} + x {}^{2}$

d)

$= (x - 3y) {}^{2}$

$= x {}^{2} - 2x \: . \: 3y + (3y) {}^{2}$

$= x {}^{2} - 6xy + 9y {}^{2}$

e)

$= (2x + 3) {}^{2}$

$= (2x) {}^{2} + 2 \: . \: 2x \: . \: 3 + 3 {}^{2}$

$= 4x {}^{2} + 12x + 9$

Att. Makaveli1996