A) \[{{\cos }^{-1}}\frac{3}{4}\]
B) \[{{\cos }^{-1}}\frac{3}{5}\]
C) \[{{\cos }^{-1}}\frac{4}{5}\]
D) \[\frac{\pi }{4}\]
Correct Answer: B
Solution :
\[|\mathbf{a}.\mathbf{b}|=ab\cos \theta =3\] ?..(i) and \[|\mathbf{a}\times \mathbf{b}|=ab\,\sin \theta =4\] ?..(ii) Dividing (ii) by (i), we get \[\tan \theta =\frac{4}{3}\Rightarrow \cos \theta =\frac{3}{5}\Rightarrow \theta ={{\cos }^{-1}}\frac{3}{5}.\]
You need to login to perform this action.
You will be redirected in
3 sec
