Remove the Symbols of Grouping, and Simplify $\left(2 x+3 y z^{2}\right)^{2}+\left(2 x-3 y z^{2}\right)^{2}-2\left(4 x^{2}+15 y^{2} z^{4}\right)$

Short Answer

Remove the symbols of grouping, and simplify: $\left(2 x+3 y z^{2}\right)^{2}+\left(2 x-3 y z^{2}\right)^{2}-2\left(4 x^{2}+15 y^{2} z^{4}\right)$