Respostas

2014-08-17T21:41:27-03:00
Olá Darinha,

2a-3b+5c+3b-2a-4c+d=2a-2a-3b+3b+5c-4c+d\\\\
\large\boxed{\boxed{2a-3b+5c+3b-2a-4c+d=c+d}}.\\.

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\large\boxed{\boxed{3a(-2ab)=-6a^2b}}.\\.

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\large\boxed{\boxed{(x+1)(x-1)=x^2-1}}.\\.

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(a-b)^2=a^2-2\cdot a\cdot b+(-b)^2\\\\
\large\boxed{\boxed{(a-b)^2=a^2-2ab+b^2}}.\\.

Tenha ótimos estudos =))