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Given a > 0, b > 0, 2C > A + B, prove (1) C ^ 2 > AB (2) C - √ C ^ 2-ab
(1) 4c^2>a^2+b^2+2ab≥2ab+2ab≥4ab
c^2>ab
(2)∵a+b0,b>0
∴a*a+a*b
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