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Bogdan Stan
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2
General complex inequality
General complex inequality
Source: G.M.
November 25, 2019
inequalities
algebra
complex numbers
Problem Statement
Prove the complex inequality
∣
x
∣
+
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y
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+
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z
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≤
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x
+
y
+
z
∣
+
∣
x
−
z
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+
∣
z
−
y
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+
∣
y
−
z
∣
.
|x|+|y|+|z|\le |x+y+z| +|x-z| +|z-y|+|y-z|.
∣
x
∣
+
∣
y
∣
+
∣
z
∣
≤
∣
x
+
y
+
z
∣
+
∣
x
−
z
∣
+
∣
z
−
y
∣
+
∣
y
−
z
∣.
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