\(13)(2x+3y)^3\\=(2x)^3+3\cdot(2x)^2\cdot 3y+3\cdot 2x\cdot (3y)^2+(3y)^3\\=8x^3+36x^2y+54xy^2+27y^3\\---\\14)(3x+2y)^3\\=(3x)^3+3\cdot(3x)^2\cdot 2y+3\cdot3x\cdot(2y)^2+(2y)^3\\=27x^3+54x^2y+36xy^2+8y^3\\---\)
\(15)(3x-2y)^3\\=(3x)^3-3\cdot(3x)^2\cdot2y+3\cdot3x\cdot(2y)^2-(2y)^3\\=27x^3-54x^2y+36xy^2-8y^3\\---\\16)(4x-y)^3\\=(4x)^3-3\cdot(4x)^2\cdot y+3\cdot4x\cdot y^2-y^3\\=64x^3-48x^2y+12xy^2-y^3\)
#\(Toru\)
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