< x , y , z > = < 2 , 1 , 2 > + < 3 , 5 , 2 > t < x , y , z > = < 2 , 5 , 2 > + < 3 , 3 , 2 > s 1. a 1 ⃗ = ( 3 , 5 , 2 ) a 2 ⃗ = ( 3 , 3 , 2 ) 3 3 ≠ 5 3 ≠ 2 2 <x,y,z>=<2,1,2>+<3,5,2>t\\
<x,y,z>=<2,5,2>+<3,3,2>s\\
1. \vec{a_1}=(3,5,2)\\
\vec{a_2}=(3,3,2)\\
\frac{3}{3}\neq\frac{5}{3}\neq\frac{2}{2} < x , y , z >=< 2 , 1 , 2 > + < 3 , 5 , 2 > t < x , y , z >=< 2 , 5 , 2 > + < 3 , 3 , 2 > s 1. a 1 = ( 3 , 5 , 2 ) a 2 = ( 3 , 3 , 2 ) 3 3 = 3 5 = 2 2
lines are not parallel
2.
A ( 2 , 1 , 2 ) , B ( 2 , 5 , 2 ) A B → = ( 2 − 2 , 5 − 1 , 2 − 2 ) = ( 0 , 4 , 0 ) A B → ⋅ a 1 ⃗ ⋅ a 2 ⃗ = = ∣ 0 4 0 3 5 2 3 3 2 ∣ = 0 ⋅ 5 ⋅ 2 + 4 ⋅ 2 ⋅ 3 + 0 ⋅ 3 ⋅ 3 − − 0 ⋅ 5 ⋅ 3 − 3 ⋅ 4 ⋅ 2 − 3 ⋅ 2 ⋅ 0 = 24 − 24 = 0 A(2,1,2), B(2,5,2)\\ \overrightarrow{AB}=(2-2,5-1,2-2)=(0,4,0)\\
\overrightarrow{AB}\cdot\vec{a_1}\cdot\vec{a_2}=\\
=\begin{vmatrix}
0 & 4&0 \\
3 & 5&2\\
3&3&2
\end{vmatrix}=0\cdot5\cdot2+4\cdot2\cdot3+0\cdot3\cdot3-\\
-0\cdot5\cdot3-3\cdot4\cdot2-3\cdot2\cdot0=24-24=0 A ( 2 , 1 , 2 ) , B ( 2 , 5 , 2 ) A B = ( 2 − 2 , 5 − 1 , 2 − 2 ) = ( 0 , 4 , 0 ) A B ⋅ a 1 ⋅ a 2 = = ∣ ∣ 0 3 3 4 5 3 0 2 2 ∣ ∣ = 0 ⋅ 5 ⋅ 2 + 4 ⋅ 2 ⋅ 3 + 0 ⋅ 3 ⋅ 3 − − 0 ⋅ 5 ⋅ 3 − 3 ⋅ 4 ⋅ 2 − 3 ⋅ 2 ⋅ 0 = 24 − 24 = 0
lines are intersecting
*If intersecting (type the number 2).
Comments