∠AED=∠B+∠BAE
=∠B+1/2∠BAC
=∠B+1/2(180º-∠B-∠C)
=90º+1/2(∠B-∠C)
∠DAE=90º-∠AED
=90º-90º-1/2(∠B-∠C)
=1/2(∠C-∠B)