A) \[{{m}^{2}}-{{n}^{2}}\]
B) \[{{m}^{2}}{{n}^{2}}\]
C) \[{{n}^{2}}-{{m}^{2}}\]
D) \[{{m}^{2}}+{{n}^{2}}\]
Correct Answer: D
Solution :
\[a\,\cos \theta +b\sin \theta =m\] Squaring both sides, we get \[{{a}^{2}}{{\cos }^{2}}\theta +{{b}^{2}}{{\sin }^{2}}\theta +2ab\,\,\cos \theta sib\theta ={{m}^{2}}\] ??(i) \[a\sin \theta -b\cos \theta =n\] Squaring both sides, we get \[{{a}^{2}}{{\sin }^{2}}\theta +{{b}^{2}}{{\cos }^{2}}\theta -2ab\cos \theta sin\theta ={{n}^{2}}\] ??(ii) Adding (i) and (ii), we get \[{{a}^{2}}+{{b}^{2}}={{m}^{2}}9{{n}^{2}}\]
You need to login to perform this action.
You will be redirected in
3 sec
