Expand the following expression.
1. -3 (2d+e) (e-2d)
Maths!!!
2008-11-03 1:39 am
回答 (2)
2008-11-03 10:54 pm
✔ 最佳答案
展開吧-3 (2d+e) (e-2d)
=-3 (2de-4d²+e²-2de)
=-3 (e²-4d²)
=-3e²+12d²
=12d²-3e²........完成
仲有簡單d
-3 (2d+e) (e-2d)
=3 (2d+e) (2d-e) .............a-b=-(b-a)
=3[(2d)²-(e)²].............(a+b)(a-b)=a²-b²
=3(4d²-e²)
=12d²-3e².......完成
參考: 會考數學拿c既人~
2008-11-03 1:41 am
-3 (2d+e) (e-2d)
= -(6d+3e)(e-2d)
= -(6de-12d^2+3e^2-6de)
= -(3e^2-12d^2)
= 12d^2-3e^2
= -(6d+3e)(e-2d)
= -(6de-12d^2+3e^2-6de)
= -(3e^2-12d^2)
= 12d^2-3e^2
參考: MY BRAIN
收錄日期: 2021-04-29 16:16:54
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