Determine the value of λ for which the following planes are perpendicular to each other.
and
Given planes, and
We know that planes and
are perpendicular if
We have and
Now,
⇒(λ + 4 – 21) = 0
⇒λ = 21 – 4 = 17
Hence, for λ = 17 the given planes are perpendicular.