Răspunsuri

2014-10-24T15:53:03+03:00
Vezi figura atasata.
Ducem mediana AM.
=> AM=BM=MC
=> <MAC=15°=> <DAM=<DAC-<MAC=75-15=60°
=> <DMA=30°
in ΔDAM
sin <DMA=AD/AM
sin 30°=1/2=AD/AM
=> AD=AM/2
dar AM=BC/2
=> AD=BC/4