Question

A line makes 45° with X axis and equal angles with Y axis and Z axis. Then the sum of these three angles is? ​

Answer 1

Answer:

As we know in 3D the relation between angles made by a vector with x axis (x),y axis (y), z axis(z) is:-

Cos^2(x)+cos^2(y)+cos^2(z)=1

So, cos^2(45)+cos^2(45)+cos^2(z)=1

1/2+1/2+cos^2(z)=1

Cos^2(z)=0

Z=90 degree

That means angle between vector and z axis is 90 degrees