Answers

2015-08-07T07:20:40+08:00
1st squared the first term minus/pkus twice the product of 1st and 2nd term and last squared the 2nd term.
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2015-08-07T18:59:11+08:00
Square of a binomial
ex.(x+y)^2 first x(x)=x^2,x(y)=xy+xy=2xy,y(y)
                    the answer is x^2+2xy+y^2
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