Connect BD and AD so that BE⊥CD is the diameter at e∫ab, and ∴∠ ACB = 90. ∵AC=6, AB= 10, according to Pythagorean theorem BC=8. ∫CD ∠ACB, ∴∠ BCD = 45. ∵BE⊥CD,∴CE=BE。 ∵BC=8, according to Pythagorean theorem, CE=BE=4√2, ∵AD=BD, AB is the diameter, ∴BD=5√2. In the right triangle BDE, BD=5√2, BE=4√2, ∴ DE = 3 √.