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The operator \(@\) is defined by the following expression: \(a@b = |\frac{a+1}{a}| - \frac{b+1}{b}\) where \(ab\neq{0}\). What is the sum of the solutions to the equation \(x@2 = \frac{x@(-1)}{2}\) ?
Re: The operator @ is defined by the following expression: a@b
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09 Apr 2020, 05:42
Expert Reply
\(\frac{1}{2}*(|\frac{x+1}{x}|)-|\frac{2+1}{2}|=0\)...... \(|\frac{x+1}{x}|=3\).... Two cases.. 1) \(\frac{(x+1)}{x}=3......x+1=3x....x=\frac{1}{2}\) 2) \(\frac{(x+1)}{x}=-3.....x+1=-3x.....x=-\frac{1}{4}\) Sum = \(\frac{1}{2}-\frac{1}{4}=\frac{1}{4}\) or 0.25
Re: The operator @ is defined by the following expression: a@b
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16 Dec 2021, 05:42
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Given that \(a@b = |\frac{a+1}{a}| - \frac{b+1}{b}\) where \(ab\neq{0}\) and we need to find the sum of all solutions of the equation \(x@2 = \frac{x@(-1)}{2}\)
Let's start by finding the value of x@2 first To find the value of x@2, compare x@2 with a@b => a=x and b=2 So, to find x@2 substitute a=x and b=2 in \(a@b = |\frac{a+1}{a}| - \frac{b+1}{b}\) => \(x@2 = |\frac{x+1}{x}| - \frac{2+1}{2}\) =\( |\frac{x+1}{x}| - \frac{3}{2}\)
Given that \(x@2 = \frac{x@(-1)}{2}\) => \( |\frac{x+1}{x}| - \frac{3}{2}\) = \(|\frac{x+1}{x}|\) / 2 => \(| \frac{x+1}{x}| - |\frac{x+1}{x}|\) / 2 =\( \frac{3}{2}\) Multiply both the sides by 2 we get \( 2*|\frac{x+1}{x}| - |\frac{x+1}{x}|\) = 3 => \(|\frac{x+1}{x}|\) = 3
We will get two cases (Watch this video to know about the basic of Absolute Value) Case 1: \(\frac{x+1}{x }\)>= 0 (0r x+1 > 0 => x > -1 and x≠0 => \(|\frac{x+1}{x}|\) = \(\frac{x+1}{x }\) => \(\frac{x+1}{x }\) = 3 => x + 1 = 3x => 2x = 1 => x = \(\frac{1}{2}\) which is > -1 so this is one solution
Case 2: \(\frac{x+1}{x }\)< 0 => \(|\frac{x+1}{x}|\) = - \(\frac{x+1}{x }\) => -\(\frac{x+1}{x }\) = 3 => -x - 1 = 3x => 4x = -1 or x = \(\frac{-1}{4}\) Let's check if this is a right answer by substituting the value in \(\frac{x+1}{x }\)< 0 ((-1/4) + 1) / (-1/4) = (3/4) / (-1/4) < 0 so this is also a solution
=> Sum of values of the solution = \(\frac{1}{2}\) + \(\frac{-1}{4}\) = \(\frac{1}{4}\) = 0.25
So, Answer will be D Hope it helps!
Watch the following video to learn the Basics of Functions and Custom Characters
Re: The operator @ is defined by the following expression: a@b
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21 Mar 2023, 21:13
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Re: The operator @ is defined by the following expression: a@b [#permalink]