Showing posts with label Derivatives of other trig functions. Show all posts
Showing posts with label Derivatives of other trig functions. Show all posts

Tuesday, January 19, 2010

Derivatives of Other Trigonometric Functions (Scribe Post for Monday's Class)

Welcome to a snowy day in Carbondale, Colorado. Today's topic of interest: The derivatives of trigonometric functions.

In the beginning of class, we reviewed a few topics from trigonometry including the reciprocal properties, the quotient properties and the Pythagorean Properties. Here are the slides from the notes we took in class. It also includes the derivations of the four other trig functions. Hope it helps!


I found the unit circle diagram for the Pythagorean Properties very helpful, but in case this is hard to read, here is a summary of the three types of properties:

#1: THE RECIPROCAL PROPERTIES:



#2: THE QUOTIENT PROPERTIES:




#3: THE PYTHAGOREAN PROPERTIES:



Ok, so now onto the fun part, the derivatives of the other trig functions. In order to discover these derivatives, we used the quotient rule.
(Just in case you forgot, the quotient rule is the derivative of numerator times the denominator minus the numerator times the derivative of the denominator all divided by the denominator squared.)

So here are our the results of our derivations for the six trigonometric functions:













In order for this to be true though, x must be in radians

Here are some of the memory aids we came up with in class:
- Derivatives of "co" functions have negative signs
-from Pythagorean Properties
+tanx goes with secx
+cotx goes with cscx
+sinx goes with cosx


Here is a short video I found helpful. It has a few examples:
3.5 Derivatives Of Trig Functions
View more presentations from ricmac25.
http://www.slideshare.net/share/blogspot/116892

REMEMBER TOMORROW IS VIRTUAL WEDNESDAY. YOU CAN CHOSE WHETHER TO COME TO CLASS OR TO DEVELOP YOUR OWN VIRTUAL LESSON. The topic is: the derivative of inverse functions.






If you have any questions at all please feel free to leave a comment.

And the next scribe is..... drum roll please.... Beston

Here is the sample derivation for secant:












Monday, January 18, 2010

Today's Slides: January 18, 2010

Hello All,
Here are the slides from today's class on discovering the derivatives of the other trigonometric functions.
Cheers, Bru