Answers

2014-07-07T22:01:43+05:30
( a+b+c )² = ( a²+b²+c²+2ab+2bc+2ca ) use this identity.
= (2x)² + (3y)² + (-3) +2*(2x)*3y + 2*(3y)*(-3) + 2*(-3)*(2x)
= 4x² + 9y² + 9 +12xy - 18y -12x
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