1.解:原式=[(2x+y)+z]²=(2x+y)²+2z(2x+y)+z²=4x²+y²+z²+4xy+4xz+2yz
2.解:原式=[(4x-5y)(4x+5y)]²=(16x²-25y²)²=256x^4-800x²y²+625y^4
3.解:原式=[2y+(x-1)][2y-(x-1)]=4y²-(x-1)²=4y²-x²+2x-1
1.解:原式=[(2x+y)+z]²=(2x+y)²+2z(2x+y)+z²=4x²+y²+z²+4xy+4xz+2yz
2.解:原式=[(4x-5y)(4x+5y)]²=(16x²-25y²)²=256x^4-800x²y²+625y^4
3.解:原式=[2y+(x-1)][2y-(x-1)]=4y²-(x-1)²=4y²-x²+2x-1