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vinni.k
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|x + 3| - |4 - x| = |8 + x| How many solutions does the equation have ?
Answer for this question is indeed 0, but i have a different query. I am having trouble in expanding this equation.
There are three key points: -8, -3, 4. So, there are 4 conditions.
(1). x < -8.
(2). -8 <= x < -3.
(3). -3 <= x < 4
(4). x >= 4
expanding for x < -8 => -(x + 3) - (4 - x) = -(8 + x)
expanding for -8 <= x < -3 => -(x + 3) - (4 - x) = (8 + x)
expanding for -3 <= x < 4 => (x + 3) - (4 - x) = (8 + x)
expanding for x >= 4 => (x + 3) + (4 - x) = (8 + x)
How to decide which modulus is positive or negative. A real big time confusion because of it many questions are getting wrong.
Please help.
Thanks & Regards
Vinni
Answer for this question is indeed 0, but i have a different query. I am having trouble in expanding this equation.
There are three key points: -8, -3, 4. So, there are 4 conditions.
(1). x < -8.
(2). -8 <= x < -3.
(3). -3 <= x < 4
(4). x >= 4
expanding for x < -8 => -(x + 3) - (4 - x) = -(8 + x)
expanding for -8 <= x < -3 => -(x + 3) - (4 - x) = (8 + x)
expanding for -3 <= x < 4 => (x + 3) - (4 - x) = (8 + x)
expanding for x >= 4 => (x + 3) + (4 - x) = (8 + x)
How to decide which modulus is positive or negative. A real big time confusion because of it many questions are getting wrong.
Please help.
Thanks & Regards
Vinni
