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If hat a and hat b are unit vectors in...

If `hat a` and `hat b` are unit vectors inclined at an angle θ then prove that : `tan (θ/2) =|hat a + hat b|/ |hat a − hatb|`

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The correct Answer is:
A
`(fogogof) (x)= sin^(2) (sin x^(2))`
`(gogof) (x) = sin (sin x^(2))`
`:. Sin^(2) (sin x^(2))= sin (sin x^(2))`
`rArr sin (sin x^(2)) [sin (sin x^(2))-1]=0`
`rArr sin (sin x^(2))=0` or `1`
`rArr sin x^(2) = npi` or `2 mpi+pi//2`, where `m, n in I`
`rArr sin x^(2)=0`
`rArr x^(2) =n pi rArr x= pm sqrt(npi), n in {0, 1, 2, ...}`.
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