Show that the following planes are at right angles:

(i) and


(ii) and


To show the right angle between two planes, we simply find the angle between the normal vectors of planes. So if n1 and n2 are normal vectors and θ is the angle between both then

.for right angle θ=90°


Cos90°=0


(1)


(i)On comparing with standard equation





Hence proved planes at right angles.


(ii) On comparing with the standard equation of a plane





Hence proved planes at right angles.


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