计算:(1)16(y+3)²(y-3)²-(2y+1)²(2y-1)²(2)(2x+y-5z)(2x+y+5z)

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计算:(1)16(y+3)²(y-3)²-(2y+1)²(2y-1)²(2)(2x+y-5z)(2x+y+5z)计算:(1)16(y+3)²(y-3)

计算:(1)16(y+3)²(y-3)²-(2y+1)²(2y-1)²(2)(2x+y-5z)(2x+y+5z)
计算:(1)16(y+3)²(y-3)²-(2y+1)²(2y-1)²(2)(2x+y-5z)(2x+y+5z)

计算:(1)16(y+3)²(y-3)²-(2y+1)²(2y-1)²(2)(2x+y-5z)(2x+y+5z)
(1)16(y+3)²(y-3)²-(2y+1)²(2y-1)²
=16[(y+3)(y-3)]²-[(2y+1)(2y-1)]²
=16(y²-9)²-(4y²-1)²
=16(y的4次方-18y²+81)-(16y的4次方-8y²+1)
=-280y²+1295
(2)(2x+y-5z)(2x+y+5z)
=[(2x+y)-5z][(2x+y)+5z]
=(2x+y)²-25z²
=4x²+4xy+y²-25z²