What is the equation of the line tangent to # f(x)=xsecx - xcosx # at # x=pi/3#? Calculus Derivatives Tangent Line to a Curve 1 Answer Sonnhard Jun 22, 2018 #y=(3/2+5*pi/(2*sqrt(3)))*x-5*pi/(6*sqrt(3))# Explanation: We get #f(pi/3)=pi/2# #f'(x)=-cos(x)+sec(x)+x*sin(x)+x*sec(x)*tan(x)# #f'(pi/3)=3/2+5*pi/(2*sqrt(3))# Answer link Related questions How do you find the equation of a tangent line to a curve? How do you find the slope of the tangent line to a curve at a point? How do you find the tangent line to the curve #y=x^3-9x# at the point where #x=1#? How do you know if a line is tangent to a curve? How do you show a line is a tangent to a curve? How do you find the Tangent line to a curve by implicit differentiation? What is the slope of a line tangent to the curve #3y^2-2x^2=1#? How does tangent slope relate to the slope of a line? What is the slope of a horizontal tangent line? How do you find the slope of a tangent line using secant lines? See all questions in Tangent Line to a Curve Impact of this question 1205 views around the world You can reuse this answer Creative Commons License