what are drs and dcs give example??
Here are the links for the answer to your query:
https://www.meritnation.com/ask-answer/question/what-s-direction-cosine-and-direction-ration-its-conf/three-dimensional-geometry/6689179
https://www.meritnation.com/ask-answer/question/between-direction-ratios-and-direction-cosines-in/three-dimensional-geometry/1607263
https://www.meritnation.com/ask-answer/question/what-s-direction-cosine-and-direction-ration-its-conf/three-dimensional-geometry/6689179
https://www.meritnation.com/ask-answer/question/between-direction-ratios-and-direction-cosines-in/three-dimensional-geometry/1607263