To verify the identity
(a+b)? = a? + b? + 3ab (a+b)
How could I do this? Please help me
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do u need to LEARN how to verify this?
you know that a^3 = a x a x a right? so just multipy (a+b) into itself three times, 
(a+b)^3=(a+b)^2 x (a+b) =( a2+b2+2ab )(a+b) now at least do the rest by yourself