Derivative of sec x

ddx[sec⁡(x)]=sec⁡(x)tan⁡(x)\frac{d}{dx}\left[\sec\left(x\right)\right] = \sec\left(x\right) \tan\left(x\right)

sec x = 1/cos x, so the chain rule (or quotient rule) gives sin x / cos²x, which is usually written sec x · tan x.

Derivation

  1. Trig rule

    ddx[sec⁡(x)]=sec⁡(x)tan⁡(x)\frac{d}{dx}\left[\sec\left(x\right)\right] = \sec\left(x\right) \tan\left(x\right)
-1-0.50.510.511.522.533.54
  • f(x) = sec x
  • f′(x)

Drag the graph · at x = 0.39 the slope is 0.44443, the height of the dashed curve.

Open in the derivative calculator

Questions students ask

What is the derivative of sec x?

ddx[sec⁡(x)]=sec⁡(x)tan⁡(x)\frac{d}{dx}\left[\sec\left(x\right)\right] = \sec\left(x\right) \tan\left(x\right).

How do you find the derivative of sec x?

sec x = 1/cos x, so the chain rule (or quotient rule) gives sin x / cos²x, which is usually written sec x · tan x.

What is the integral of sec x?

See the integral of sec x page for the antiderivative with steps.