maths 功課唔識做 今晚9:30要

1.(6x[2]-4x+3)(2x-1)
=12x[3] -6x[2] -8x[2] -3
=12x[3] -14x[2] -3

2.(4w{2}-w)(1-5w+7w[2])
=4w[2] -20w[3] +28w[4] -w +5w[2] -7w[3]
=28w[4] -27w[3] +9w[2] -w

3.3(2c-5d)(2c[3]-5cd-3d)
=3(4c[4] -10c[2]d -6cd -10c[3]d +25cd[2] +15d[2]
=12c[4] +30c[2]d -18cd -30c[3]d +75cd[2] +45d[2]

4.(2a+3)(2a-1)
=4a[2] -2a +6a -3
=4a[2] +4a -3

5.(6-2c)+(3d+2)(2c+d)÷2
條數係(6-2c)+(3d+2)(2c+d)÷2
(6-2c)+(3d+2)(2c+d)÷2
=6-2c+(6cd+3d[2]+4c+2d)÷2
=6-2c+3cd+1.5d[2]+2c+d
=1.5d[2]+d+6+3cd