Question

ajudem pfvr.....
pfvr​

Answer 1

Resposta:

Explicação passo a passo:

$Regras...$

$(a+b).(a-b)=a^{2}-b^{2}$

$(a+b)^{2} =a^{2} +2ab+b^{2}$

$(a-b)^{2} =a^{2} -2ab+b^{2}$

$a)$

$(8x+1).(8x-1)=(8x)^{2} -(1)^{2}=64x^{2} -1$

$b)$

$(10+3x)^{2} =10^{2} +2.10.3x+(3x)^{2} =100+60x+9x^{2}$

$c)$

$(7a-b)^{2} =(7a)^{2} -2.7a.b+b^{2} =49a^{2} -14ab+b^{2}$

$d)$

$(x+0,5y)^{2} =x^{2} +2.x.(0,5)+(0,5y)^{2} =x^{2} +x+0,25y^{2}$

$e)$

$(ax+b).(ax-b)=(ax)^{2}-(b)^{2} =a^{2} x^{2} -b^{2}$

$f)$

$(a^{2}-4y) ^{2} =(a^{2}) ^{2} -2.a^{2} .4y+(4y)^{2} =a^{4}-8a^{2}y+16y^{2}$