1/x-1 - 1/x
Q2
x/x+y + y/x-y
STEPS PLEASE
更新1:
WHY [x-(x-1)]?
F.2 MATHS
回答 (1)
2007-10-01 12:07 am
✔ 最佳答案
1. 1/x-1-1/x=x(1)/x(x-1)-1(x-1)/x(x-1)
=x/x(x-1)-x+1/x(x-1) 找最小公倍數
=1/x(x-1)
2.x/x+y +y/x-y
=x(x-y)/(x+y)(x-y) +y(x+y)/(x+y)(x-y)
=x^2-xy/(x+y)(x-y)+xy+y^2/(x+y)(x-y) Don't expand the denominator
=x^2+y^2/(x+y)(x-y)
唔知對不對,自己驗算
收錄日期: 2021-04-18 23:27:07
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https://hk.answers.yahoo.com/question/index?qid=20070930000051KK02862