Janek191:
→
u = [ − 2, 0, 1 ]
→
v = [ 0 , 1 , − 2]
więc
→ →
u o v = −2*0 + 0*1 + 1*(−2) = − 2
oraz
u =
√(−2)2 + 02 + 12 =
√5
v =
√02 + 12 + (2)2 =
√5
→ → → →
| | u o v | | − 2 | | −2 | |
b) cos ∡ ( u , v ) = |
| = |
| = |
| = − 0,4 |
| | u * v | | √5*√5 | | 5 | |
→ →
I ∡ ( u , v ) I = 113
o 30 '
=======================
a)
→ → →
w = u + v = [ − 2, 0 , 1] + [ 0, 1 , − 2] = [ − 2, 1, − 1]
więc
w =
√ (−2)2 + 12 + (−1)2 =
√ 4 + 1 + 1 =
√6
========================================