MathDB

3

Part of 2017 Kyrgyzstan Regional Olympiad

Problems(1)

inequality algebra

Source: kYRGYZSTAN REGIONAL

3/7/2017
If ∣x∣<1 {|x|}<{1} and ∣y∣<1{|y|}<1 then prove that ∣x−y1−xy∣<1|\frac{x-y}{1-xy}|<1
inequalities