(h-4)既三次方 係幾多?

(h - 4) x (h - 4) x (h - 4)
= [h(h - 4) - 4(h - 4)] x (h - 4)
= (h^2 -4h - 4h + 16) x (h - 4)
= (h^2 - 8h + 16) x (h - 4)
= h(h^2 - 8h + 16) - 4(h^2 - 8h + 16)
= h^3 - 8h^2 + 16h - 4h^2 + 32h - 64
= h^3 - 12h^2 + 48h - 64

(h-4)x(h-4)x(h-4)

=(h-4)(h-4)x(h-4)

=[h(h-4)-4(h-4)]x(h-4)

=(h^2-4h-4h+16)x(h-4)

=(h^2-8h+16)x(h-4)

=h(h^2-8h+16)-4(h^2-8h+16)

=h^3-8h^2+16h-4h^2+32h-56

=h^3-12h^2+48h-56

用公式可以咁:(本人只是中二)
(h-4)(h-4)(h-4)

=[h^2-2(h)(4)+(4)^2](h-4)
=(h^2-8h+16)(h-4)
=h^3-4h^2-8h^2+24h+16h-64

=h^3-12h^2+40h-64

本人只是中二,可能未學到其他可計算這式的公式。

2007-03-27 19:35:20 補充：
oh sor第3步write錯=h^3-4h^2-8h^2 32h 16h-64=h^3-12h^2 48h-64

(h-4)x(h-4)x(h-4)
=(h^2-8h+16)(h-4)
=h^3-4h^2-8h^2+32h+16h-64
=h^3-12h^2+48h-64