Given A2 + B2 = C2 + D2 = 1, find the value of (AC BD) 2 + (AD + BC) 2 Please write the process in detail, I wait online, please hurry up! Thank you!
∵a²+b²=c²+d²=1∴(a²+b²)(c²+d²)=a²c²+a²d²+b²c²+b²d²=1∴(ac-bd)²+(ad+bc)²=a²c²-2abcd+b²d²+a...
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