Question 1. For which values of a
parameter a∈ℝ
have the vectors u=(1,a,2), v=(2,-a,1)
the deviation 60° ?
a)a∈{-1,2}
b)a∈{-3,3}
c) for none a
d)a=1
e)a∈{-1,1}
Question 2.
Given the straight line X=[-3,2]+t(4,-1), t∈ℝ.
Determnie the values of a parameter t for
which the points of the straight line are within the first quadrant.
a)t∈(-∞,34⟩
b)t∈⟨34,∞)
c)t∈(-∞,2⟩
d)t∈⟨2,∞)
e)t∈⟨34,2⟩
Question 3.
The distance of the plane x+2y-2z+7=0
from X=[5,0,0]+t(0,1,1)+u(2,0,1), t,u∈ℝ
is equal to