When the signs of the terms of a binomial being squared are different, which term of the resulting trinomial will be negitive?

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1 Answer
Jensen Z
Feb 22, 2018

I'm assuming you mean the blue in

#(xcolor(blue)(+)y)^2 and (xcolor(blue)(-)y)^2#

Squaring a binomial #(x+y)# gives #x^2+2xy+y^2#

Squaring a binomial #(x-y)# gives #x^2-2xy+y^2#.

As you can see, the middle term changes.

#---------------#

Example:

#(x+3)^2# is #x^2+6x+9#

#(x-3)^2# is #x^2-6x+9#

As you can see, the middle term changes.

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