Yet another inequality question
Favorites|Homepage
Subscriptions | sitemap
HOME > Mathematics > Yet another inequality question

Yet another inequality question

[From: ] [author: ] [Date: 11-10-09] [Hit: ]
Hence y² > 9 is the only possibility and, as you say, the answer is y 3.-Glad to help!......
The question is composed of two parts:
(a) Use algebrato find the set of valuesof x for which x(x - 5) > 36

I found the answer x < -4, x > 9

The second part is the one I'm having trouble with.

(b) Using your answer to part [a], find the set of values of y for which y^2(y^2 - 5) > 36

I'm not sure how I'm going to use the answer from part 1 in part 2. I'm not sure where to begin answering this question. The answer is y < -3, y > 3
Can someone please explain this to me.

-
If you set x = y², the solution to part (a) tells you that y² < -4 or y² > 9.
But y² < -4 is impossible because that would imply y² is negative, which is impossible.
Hence y² > 9 is the only possibility and, as you say, the answer is y < -3 or y > 3.

-
Glad to help!

Report Abuse

1
keywords: another,Yet,inequality,question,Yet another inequality question
New
Hot
© 2008-2010 http://www.science-mathematics.com . Program by zplan cms. Theme by wukong .