find dy/dx

y=ln (secx + tanx)

Let u= secx + tan x

dy/dx= 1/u * du/dx

now, put the derivative of d secx/dx + dtanx/dx in. You may have some challenging algebra to simplify it.

Use the chain rule. Let y(u) = ln u
u(x) = sec x + tan x
dy/dx = dy/du*du/dx

dy/du = 1/u = 1/(sec x + tan x)
dy/dx = sec x tan x + sec^2 x
= sec x (sec x + tan x)
dy/dx = sec x

(sec x + tan x)

So, the derivative dy/dx of y = ln(sec x + tan x) is:

dy/dx = (sec x)(sec x + tan x) / (sec x + tan x)
dy/dx = sec x.

dy/dx = sec x

To find dy/dx, we start by letting u = secx + tanx. Now we have the function y = ln(u), and we want to find dy/dx.

Using the chain rule, we have dy/dx = dy/du * du/dx.

First, we need to find dy/du. We know that the derivative of ln(u) is 1/u. Therefore, dy/du = 1/u.

Next, we need to find du/dx. Since u = secx + tanx, we can find du/dx using the derivative rules for secant and tangent functions. The derivative of secx is secx * tanx, and the derivative of tanx is sec^2x. Therefore, du/dx = secx * tanx + sec^2x.

Now, we can substitute the values we found into our equation for dy/dx.

dy/dx = dy/du * du/dx
= (1/u) * (secx * tanx + sec^2x)

Substituting u = secx + tanx, we have:

dy/dx = (1/(secx + tanx)) * (secx * tanx + sec^2x)

Simplifying the expression, we get:

dy/dx = secx

So, the derivative of y = ln(secx + tanx) with respect to x is dy/dx = secx.