Question

If f(x) = secx + e*. find f(x) using first principle of derivatives.

Answer 1

Answer:

Let f(x)=secx

∴f(x+h)sec(x+h)

dxdf(x)=h→0lim[hf(x+h)−f(x)]

dxd(secx)=h→0lim[hsec(x+h)−secx]

dxd(secx)=h→0lim[h1(cos(x+h)1−cosx1)]

dxd(secx)=h→0lim[h1(cos(x+h)cosxcos(x)−cos(x+h))]

dxd(secx)=h→0lim⎣⎢⎢