Find the values of x for which the angle between the vectors `veca=-3hati+xhatj+hatk and vecb=xhati+2xhatj+hatk` is acute nd the angle between `vecb` and x-axis lies between `pi/2 and pi.

The values of x for which the angle between the vectors veca = xhati - 3hatj - hatk and vecb = 2xhati + xhatj - hatk is acute and the angle between b and y-axis lies between pi/2 and pi are:

Find the values of x for which the angle between the vectors veca=2xhati+4xhatj+hatk and vecb=7xhati-2hatj+xhatk is obtuse.

Find the angle between the vectors : veca=3hati-2hatj+hatk and vecb=hati-2hatj-3hatk .

Find the angle between the vectors veca=hati-hatj+hatk and vecb=hati+hatj-hatk .

Find the angle between the vectors veca=hati+hatj-hatk and vecb=hati-hatj+hatk

Find the angle between the vectors veca=hati-hatj+hatk and vecb=hati+hatj-hatk .

Find the angle between the vectors : veca=hati+hatj-hatk and vecb=hati-hatj+hatk .

Find the angle theta between the vectors veca=hati+hatj-hatk and vecb=hati-hatj+hatk