Question

??????????????? Rápido

Answer 1

Resposta:

Explicação passo a passo:

$Regras...$

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

$(a+b)^{3} =a^{3}+3a^{2} b+3ab^{2} +b^{3}$

$a)$

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

$(3x+y)^{2} =9x^{2} +6xy+y^{2}$

$b)$

$(2x+3y)^{3}=(2x)^{3}+3.(2x)^{2}.3y+3.2x.(3y)^{2}+(3y)^{3}$

$(2x+3y)^{3}=8x^{3}+3.4x^{2} .3y+3.2x.9y^{2} +27y^{3}$

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

$c)$

$(5+x)^{2} =5^{2} +2.5.x+x^{2}$

$(5+x)^{2} =25+10x+x^{2}$