A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 5 years ago
Why can't the mean proportional be negative?
anonymous
 5 years ago
Why can't the mean proportional be negative?

This Question is Closed

dumbcow
 5 years ago
Best ResponseYou've already chosen the best response.1"mean proportional" ?? not sure what you mean

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0when a/b = b/d, then b is the mean proportional.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oops, i mean a/b=b/c. not that it makes a difference.

dumbcow
 5 years ago
Best ResponseYou've already chosen the best response.1oh ok , and to answer your question, not sure it can't be negative but it doesn't make a difference really a/b = b/c > b^2 = ac > b = +sqrt(ac) usually ratios deal with lengths which by definition are always positive

dumbcow
 5 years ago
Best ResponseYou've already chosen the best response.1example: say b = 3, a = 1, c = 9 1/3 = 3/9 , the negative cancels out so the proportion is equivalent to 1/3 = 3/9

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ah....i see. i understood that the negative cancels out (which is why i sort of asked the question, because my textbook says mean proportional can't be negative). and is it true, ratios are defined to be positive things?Thenn that would make sense.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Thanks for answering, btw. :) And i find it amusing we both have the same name almost, dumb cow and dumb duck :D

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0But the question is still unanswered :/

dumbcow
 5 years ago
Best ResponseYou've already chosen the best response.1i agree, sorry I don't have a sophisticated mathematical reason for you I have never considered it before

dumbcow
 5 years ago
Best ResponseYou've already chosen the best response.1http://regentsprep.org/Regents/math/geometry/GP12/LMeanP.htm look at definition. It is just positive by definition

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh!. i didn't know that.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0am i allowed to ask now, why they defined it to be positive? :P

dumbcow
 5 years ago
Best ResponseYou've already chosen the best response.1It comes from the definition of a function y = +sqrt(x) is not a function because it does not pass the vertical line test y = sqrt(x) is however, so the mean proportional is always positive

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ah. how come it has to be a function?

dumbcow
 5 years ago
Best ResponseYou've already chosen the best response.1http://en.wikipedia.org/wiki/Geometric_mean#cite_note1 it applies only to positive numbers, and it wouldn't make sense if the mean of positive numbers were negative

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I didn't comprehend fully.....but ah, thanks anyway. I'll keep asking why forever lol.
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.