Find a vector 
of magnitude 
making an angle π/4 with x - axis, π/2 with y - axis and an acute angle θ with z - axis.
|
| = 5√2
l = cos α = cos π/4 = 1/√2
m = cos β = cos π/2 = 0
n = cosθ
we know that
l2 + m2 + n2 = 1
since the vector makes an acute angle with the z axis
∴ 
∴ 
= |
|(l
+ m
+ n
)
∴ 
= 5√2(1/√2
+ 1/√2
)
∴ 
= 5(
)
Ans:
= 5(
)
1