Three Dimensional Geometry Question 369
If a line in the space makes angle $ \alpha ,\beta $ and $ \gamma $ with the coordinate axes, then $ \cos 2\alpha +\cos 2\beta +\cos 2\gamma +{{\sin }^{2}}\alpha +{{\sin }^{2}}\beta +{{\sin }^{2}}\gamma $ equals. test- The two given expressions on both the sides of the $ ‘=’ $ sign will have the same value if two numbers from either side or both sides are interchanged. Select the correct numbers to be interchanged from the given options. $ 3+5\times 4-24\div 3=7\times 4-3+36\div 6 $
Options:
-1
0
1
2
Show Answer
Answer:
Correct Answer: C
Solution:
$ \cos 2\alpha +\cos 2\beta +\cos 2\gamma +{{\sin }^{2}}\alpha $ $ +{{\sin }^{2}}\beta +{{\sin}}^{2}\gamma $ $ ={{\cos }^{2}}\alpha +{{\cos }^{2}}\beta +{{\cos }^{2}}\gamma =1 $