1、(1)3 9
(2)-1 -3
(3)±8或±16
(4)18 2
(5)6 1/2
2、解:(a+4)(3/4a+4)
=3/4a²+4a+3a+16
=3/4a²+7a+16(cm²),
所以这幅摄影作品(带相框)的面积为(4a²+7a+16) cm².
4、解:x²+y²=(x+y) ²-2xy
=3²-2×1=7.
5、解:(1) (2-3y) (9y²+6y+4)
=18y²+12y+8-27y³-18y²-12y
=8-27y³.
(2)(x+2) -(x-2)³
=(x+2)(x²+4x-+4)-(x-2)(x2-4x+4)
=x³+4x²+4x+2x²+8x+8-(x³- 4x²+4x-2x²+8x-8)
=12x²+16.