1.If x∈[−5π2, 5π2]x \in \left[ -\dfrac{5\pi}{2},\; \dfrac{5\pi}{2} \right]x∈[−25π,25π], then the greatest positive solution of 1+sinx=cos23x1 + \sin x = \cos^2 3x1+sinx=cos23x isa.π\piπb.2π2\pi2πc.5π2\dfrac{5\pi}{2}25πd.None of theseLogin to continueOnly logged in users canattempt or see the solution.