How do you calculate the derivative of #r= 2thetasqrt(sec theta)#? Calculus Basic Differentiation Rules Chain Rule 1 Answer Truong-Son N. Jul 9, 2015 Here we have #r(theta) = 2thetasqrtsectheta# #((dr)/(d theta))[f(theta)g(theta)] = f(theta)g'(theta) + g(theta)f'(theta)# #= (2theta)(1/(2sqrtsectheta)*secthetatantheta) + (sqrtsectheta)(2)# #= thetasqrtsecthetatantheta + 2sqrtsectheta# #= 2sqrtsectheta + thetasqrtsecthetasintheta/costheta# #= color(blue)(2sqrtsectheta + thetasinthetasec^"3/2"theta)# Answer link Related questions What is the Chain Rule for derivatives? How do you find the derivative of #y= 6cos(x^2)# ? How do you find the derivative of #y=6 cos(x^3+3)# ? How do you find the derivative of #y=e^(x^2)# ? How do you find the derivative of #y=ln(sin(x))# ? How do you find the derivative of #y=ln(e^x+3)# ? How do you find the derivative of #y=tan(5x)# ? How do you find the derivative of #y= (4x-x^2)^10# ? How do you find the derivative of #y= (x^2+3x+5)^(1/4)# ? How do you find the derivative of #y= ((1+x)/(1-x))^3# ? See all questions in Chain Rule Impact of this question 2285 views around the world You can reuse this answer Creative Commons License