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Challenge 339: Larger Product
Can you prove these inequalities?
Four numbers a, b, c and d satisfy the conditions:
a > b > c > d > 0
a + d = b + c
Prove that
(i) ac > bd
(ii) ad < bc
Can you prove these inequalities?
Four numbers a, b, c and d satisfy the conditions:
a > b > c > d > 0
a + d = b + c
Prove that
(i) ac > bd
(ii) ad < bc