Question 1. For which values of
a parameter α∈ℝ
are the vectors u=(α,α+1,-8), v=(5,α,2)
perpendicular?
a)α∈{-2,8}
b)α∈{-2,-8}
c)α=-2
d)α∈{2,-8}
e)α∈{2,8}
Question 2.
The straight line which passes through the point [2,1] and
the intersection of lines x=s, y=5+2s, s∈ℝ and x=1+3t, y=-t, t∈ℝ has
the equation
a)3x+y-7=0
b)3x-y+5=0
c)y-1=0
d) does not exist
e)-x-2y+4=0
Question 3.
The distance of the point A=[4,-1,7]
from the plane 2x+5y+z+50=0
is