Thank you for the detailed reply, can I ask you on step 3 of your workings where the 1 comes from, I can't understand it, sorryRobegk, I got this:
\(\displaystyle (x - y)^2 \ + \ 3(y - x)^3 \ = \)
\(\displaystyle (x - y)^2 \ - \ 3(x - y)^3 \ = \)
\(\displaystyle (x - y)^2[1 - 3(x - y)] \ =\)
\(\displaystyle (x - y)^2(1 - 3x + 3y) \ = \)
\(\displaystyle (x - y)^2(-3x + 3y + 1)\)
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What did you get?
Hi Robegk. He factored out the expression (x-y)^2. Like this pattern:where the 1 comes from