To find the equation of a line, we need the slope of the line and a point on the line. Since we are requested to find the equation of the tangent line at the point (4, 2), we know that (4, 2) is a point on the line. So we just need to find its slope. The slope of a tangent line to f(x) at x = a can be found using the formula

and x=4

Step-by-step explanation:

We are given that a curve

We have to find the equation of tangent at point (4,2) on the given curve.

Let y=f(x)

Differentiate w.r.t x

By using the formula

Substitute x=4

Slope of tangent

In given question

By comparing we get a=4

Point-slope form

Using the formula

The equation of tangent at point (4,2)

sorry, i can't understand your question. will later if you describe more clearly!

: )