If `veca =(2hati - 4hatj +5hatk)` then find the value of `lambda` so that `lambda veca` may be a unit vector.

If veca = (2hati - 4hatj + 5hatk) then find the value of lambda so that lambdaveca may be a unit vector.

If veca=hati-hatj+7hatk and vecb=5hati-hatj+lambdahatk , then find the value of 'lambda' , so that veca+vecb and veca-vecb are perpendicular vectors.

If veca=5hati-hatj+7hatk and vecb=hati-hatj-lambdahatk , then find the value of 'lambda' for which (veca+vecb) and (veca-vecb) are orthognal.

The scalar product of the vector veca=hati+hatj+hatk with a unit vector along the sum of vectors vecb=2hati+4hatj-5hatk and vecc=lambdahati+2hatj+3hatk is equal to one. Find the value of 'lambda' and hence find the unit vector along vecb+vecc .

If veca = (3hati + hatj - 5hatk) and vecb = (hati + 2hatj - hatk) then find a unit vector in the direction of (veca-vecb) .

If veca=4hati-hatj+hatk and vecb= 2hati-2hatj+hatk , then find a unit vector parallel to the vector veca + vecb .

If veca = (hati - 2hatj -3hatk) and vecb = (2hati + 4hatj +9 hatk) then find a unit vector parallel to (veca + vecb) .