JEE Main 2017Session, Shift 1MathematicsMediumTrigonometry118× since 2002If 5(tan2x−cos2x)=2cos2x+95\left( {{{\tan }^2}x - {{\cos }^2}x} \right) = 2\cos 2x + 95(tan2x−cos2x)=2cos2x+9, then the value of cos4x\cos 4xcos4x is :AOption A. 13{1 \over 3}31BOption B. 29{2 \over 9}92COption C. −79- {7 \over 9}−97DOption D. −35- {3 \over 5}−53CheckSkip · show solution
