Answer:
16x^2 -48xy^3 +36y^6
Explanation:
Use FOIL or the distributive property or the form of the square of a binomial to expand the square.
(4x -6y^3)(4x -6y^3) = 4x(4x -6y^3) -6y^3(4x -6y^3)
= (4x)^2 -(4x)(6y^3) -(6y^3)(4x) +(6y^3)^2
= 16x^2 -48xy^3 +36y^6
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The form referred to above is ...
(a +b)^2 = a^2 +2ab +b^2