How Many Integers Satisfy This Inequality?

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The inequality $$|||x+9|-18|-98| \le 82$$ has been analyzed to determine the number of integer solutions. The discussion concludes that there are 330 integer solutions derived from the conditions set by the absolute values involved. However, one participant claims to have found 332 solutions, prompting a request for verification of the calculations. The key steps involve evaluating the expression under different cases of the absolute values.

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How many integers satisfy the following relation?

$$|||x+9|-18|-98| \le 82$$
 
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anemone said:
How many integers satisfy the following relation?

$$|||x+9|-18|-98| \le 82$$

if we put x + 9 >= 0 we get

- 82 <= | x- 9 | - 98 <= 82

so 165 solutions as |x -9| - 98 can be atleast -98

similarly if we put | x+ 9| <= 0 so 165 solutions

so 330 solutions
 
kaliprasad said:
...

so 330 solutions

BUT...I got 332.
 
anemone said:
BUT...I got 332.

I would like to have a look at the correct solution
 
My solution:

We have two cases to consider here, one is when $x+9\ge 0$ and the other is when $x+9< 0$.If $x+9\ge 0$ (i.e. $x \ge -9$), then the inequality becomes

$$||x+9-18|-98| \le 82$$

$$||x-9|-98| \le 82$$

[TABLE="class: grid, width: 500"]
[TR]
[TD]i.[/TD]
[TD]ii.[/TD]
[/TR]
[TR]
[TD]Now, let $x-9\ge 0$ (i.e. $x \ge 9$), we have[/TD]
[TD]Now, let $x-9< 0$ (i.e. $x \ge 9$), we have[/TD]
[/TR]
[TR]
[TD]$$|x-9-98| \le 82$$

$$|x-107| \le 82$$

$$-82 \le x-107 \le 82$$

$$25 \le x \le 189$$[/TD]
[TD]$$|-(x-9)-98| \le 82$$

$$|-x-89| \le 82$$

$$-82 \le -x-89 \le 82$$

$$-171\le x \le -7$$[/TD]
[/TR]
[TR]
[TD]View attachment 1395

The number of integers that satisfy the aforementioned relation is thus $165$.[/TD]
[TD]View attachment 1396

The number of integers that satisfy the aforementioned relation in this particular case is thus $2$.[/TD]
[/TR]
[/TABLE]

But if $x+9< 0$ (i.e. $x<-9$), then the inequality becomes

$$||-x-9-18|-98| \le 82$$

$$||-x-27|-98| \le 82$$

[TABLE="class: grid, width: 500"]
[TR]
[TD]i.[/TD]
[TD]ii.[/TD]
[/TR]
[TR]
[TD]Now, let $-x-27\ge 0$, we have[/TD]
[TD]Now, let $-x-27< 0$, we have[/TD]
[/TR]
[TR]
[TD]$$|-x-27-98| \le 82$$

$$|-x-125| \le 82$$

$$-207 \le x \le -43$$[/TD]
[TD]$$|-(-x-27)-98| \le 82$$

$$|x-71| \le 82$$

$$-11\le x \le 153$$[/TD]
[/TR]
[TR]
[TD]The number of integers that satisfy the aforementioned relation is thus $165$.[/TD]
[TD]The number of integers that satisfy the aforementioned relation in this particular case is thus $2$.[/TD]
[/TR]
[/TABLE]

Therefore, the total number of integers satisfy the relation $$|||x+9|-18|-98| \le 82$$ is $165+3+165+2=335$.

Hey kaliprasad, I'm sorry because according to my previous reply, I told you the answer that I've gotten was 332, which isn't the correct answer. :o
 

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