Sketching Tangent and Normal Lines Together with the Function

How to define a function?

[Graphics:Images/TangentLine_gr_1.gif]

How to sketch the graph of the function?

[Graphics:Images/TangentLine_gr_2.gif]

[Graphics:Images/TangentLine_gr_3.gif]

[Graphics:Images/TangentLine_gr_4.gif]

How to find the equation of the tangent line?

Equation of the tangent line to the graph of the function f(x) at the point x=a is g(x)=f'(a)(x-a)+f(a). Using this formula we have

[Graphics:Images/TangentLine_gr_5.gif]
[Graphics:Images/TangentLine_gr_6.gif]
[Graphics:Images/TangentLine_gr_7.gif]

How to graph the function together with the tangent line at a point?

[Graphics:Images/TangentLine_gr_8.gif]

[Graphics:Images/TangentLine_gr_9.gif]

[Graphics:Images/TangentLine_gr_10.gif]

How to find the equation of the normal line?

Equation of the normal line to the graph of the function f(x) at the point x=a is g(x)=[Graphics:Images/TangentLine_gr_11.gif]+f(a). Using this formula we have

[Graphics:Images/TangentLine_gr_12.gif]
[Graphics:Images/TangentLine_gr_13.gif]
[Graphics:Images/TangentLine_gr_14.gif]
[Graphics:Images/TangentLine_gr_15.gif]

[Graphics:Images/TangentLine_gr_16.gif]

[Graphics:Images/TangentLine_gr_17.gif]

Homework

Problem 1

Consider the function f(x) = sin (x).

(a) Find the equation of the tangent line at x = [Graphics:Images/TangentLine_gr_18.gif].

(b) Find the equation of the normal line at x = [Graphics:Images/TangentLine_gr_19.gif].

(c) Sketch the graphs of the function, the tangent line, and the normal line on the same xy-plane.


Converted by Mathematica      February 2, 2000