Difference between revisions of "2004 AMC 10A Problems/Problem 15"
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+ | == Solution 3== | ||
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+ | As <math>-4\leq x\leq-2</math>, we know that the denominator of our given fraction is negative. So to achieve the greatest value possible, our numerator, or <math>x+y</math> must also be as small as possible. | ||
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+ | So we pick our smallest value for <math>y</math>, which is <math>2</math>. | ||
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+ | Now if we if set our value of <math>x</math> to its lowest, our expression becomes <math>\frac{(-2+2)}{-2} = \frac{0}{2}</math> | ||
== Solution 3== | == Solution 3== |
Revision as of 07:11, 22 December 2020
Problem
Given that and , what is the largest possible value of ?
Solution
Rewrite as .
We also know that because and are of opposite sign.
Therefore, is maximized when is minimized, which occurs when is the largest and is the smallest.
This occurs at , so .
Solution 2
If the answer choice is valid, then it must satisfy . We use answer choices from greatest to least since the question asks for the greatest value.
Answer choice . We see that if then
and . However, is not in the domain of , so is incorrect.
Answer choice , however, we can find a value that satisfies which simplifies to , such as .
Therefore, is the greatest.
Solution 3
As , we know that the denominator of our given fraction is negative. So to achieve the greatest value possible, our numerator, or must also be as small as possible.
So we pick our smallest value for , which is .
Now if we if set our value of to its lowest, our expression becomes
Solution 3
See also
2004 AMC 10A (Problems • Answer Key • Resources) | ||
Preceded by Problem 14 |
Followed by Problem 16 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
All AMC 10 Problems and Solutions |
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