ddxsecx=\dfrac{d}{dx}\sec x =dxdsecx=Asec2x\sec^2 xsec2xBsecxtanx\sec x \tan xsecxtanxcheck_circleC−secxtanx-\sec x \tan x−secxtanxDtanx\tan xtanxExplanationStandard derivative: secxtanx\sec x \tan xsecxtanx.