Задача 56464 УМОЛЯЮ, ПОМОГИТЕ...

5fe39a2b1c6d1142ab517092

23.12.2020 22:30:38

УМОЛЯЮ, ПОМОГИТЕ

5f3ea7e3faf909182968ddd9

23.12.2020 22:46:52

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По теореме Пифагора АС=10

1) cos ∠ (vector{AC},vector{AB})=|AB|/|AC|=6/10

vector{AC}*vector{AB}=|vector{AC}|*|vector{AB}}* cos ∠ (vector{AC},vector{AB})=10*6*6/10=[b]36[/b]

2) BD=AC=10
cos ∠ (vector{AB},vector{BD})=cos ∠ (vector{BC},vector{BD})=|CD|/|BD|=6/10

vector{AD}*vector{BD}=|vector{AD}|*|vector{BD}}* cos ∠ (vector{BC},vector{BD})=8*10*(6/10)=48