Current location - Training Enrollment Network - Mathematics courses - Special topics on high school mathematics
Special topics on high school mathematics
Solution: (1) Proof: Link OC

BO = DO,AB=AD,?

∴AO⊥BD

BO = DO,BC=CD,?

∴CO⊥BD

In △AOC, it is known that AO= 1 and CO=√3.

And AC=2,

∴AO? +CO? =AC2,?

∴∠ AOC = 90, that is, AO⊥OC.

∫BD∩OC = O

∴AB⊥ aircraft BCD.

(2) Take the midpoint M of AC to connect OM, ME and OE, and let E be the midpoint of BC to know ME∨AB, OE∨DC.

The acute angle formed by OE and EM is the angle formed by AB and CD.

Please accept it if you are satisfied, thank you!