Question

5- Calcule utilizando produtos notáveis: (valor 4,0) a) (x + y)² = b) (4m² – 1)² = c) (7x + 5z) · (7x – 5z) = d) (2x – 3y)³ =

Answer 1

Oie, Td Bom?!

a)

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

$= x {}^{2} + 2xy + y {}^{2}$

b)

$= (4m {}^{2} - 1) {}^{2}$

$= (4m {}^{2} ) {}^{2} - 2 \: . \: 4m {}^{2} \: . \: 1 + 1 {}^{2}$

$= 16m {}^{4} - 8m {}^{2} + 1$

c)

$= (7x + 5z) \: . \: (7x - 5z)$

$= (7x) {}^{2} - (5z) {}^{2}$

$= 49x {}^{2} - 25z {}^{2}$

d)

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

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

$= 8x {}^{3} - 3 \: . \: 4x {}^{2} \: . \: 3y + 3 \: . \: 2x \: . \: 9y {}^{2} - 27y {}^{3}$

$= 8x {}^{3} - 36x {}^{2} y + 54xy {}^{2} - 27y {}^{3}$

Att. Makaveli1996