Simplify the following expression:
1/c 1/d
-------------
c/d - d/c
回答 (8)
✔ 最佳答案
assume you mean
1/c+ 1/d
-------------
c/d - d/c
= 1/(c-d)
so how to solve this problem: (1/c 1/d) / (c/d - d/c)
first find the equivalent of c/d - d/c... put it in one fraction...
= (c/d - d/c)
find the LCD which is dc
= (d - c) / dc
then substitute it in the 1st expression...
= (1/c 1/d) / (c/d - d/c)
= 1/c x 1/d x (dc / d-c)
multiply reciprocal when dividing
cancel cd...
so the final answer is:
1
--------
d - c
hope that helps!!! :)
[1/cd]/[(cc-dd)/cd]=1/[cc-dd]
1/cd/c^2-d^2/cd
1/c^2-d^2
(1/c + 1/d)/(c/d - d/c)
= (d/cd + c/cd)/(c^2/cd - d^2/cd)
= [(d + c)/cd]/[(c^2 - d^2)/cd]
= [(d + c)/cd][cd/(c^2 - d^2)]
= cd(d + c)/cd(d + c)(c - d) (cancel out cd , d + c)
= 1/(c - d)
1/c + 1/d
-------------
c/d - d/c
multiply top and bottom by cd
(d+c) / (c² - d²)
(d+c) / (c+d)(c-d)
1/(c-d)
.
1/c + 1/d = (c + d)/cd
Now,
c/d - d/c = (c² - d²)/dc = [(c + d)(c - d)]/dc
Now then:
[(c + d)/cd]/[(c + d)(c - d))/cd]
= [(c + d)/cd][cd/(c + d)(c - d))]
= 1/(c - d)
Hope this helps!
收錄日期: 2021-05-01 10:56:28
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