JEE Main 201610 Apr, Morning shiftMathematicsEasyLimit, Continuity and Differentiability420× since 2002Let f(x) = sin⁴x + cos⁴ x. Then f is an increasing function in the interval :AOption A. ]0,π4[] 0, \frac{\pi}{4}[]0,4π[BOption B. ]π4,π2[] \frac{\pi}{4}, \frac{\pi}{2}[]4π,2π[COption C. ]π2,5π8[] \frac{\pi}{2}, \frac{5 \pi}{8}[]2π,85π[DOption D. ]5π8,3π4[] \frac{5 \pi}{8}, \frac{3 \pi}{4}[]85π,43π[CheckSkip · show solution
