BLAAAAHHHHH!!!

This is David on Mary's blog thing. I don't feel like creating my own account so I'm just going to share this one with Mary.

But actually having something to do with the class, I need to take better notes. I am having a bit of trouble with 7-1 through, well, everything but 7-4.

I get most of the sine and cosine functions. I understand the unit circle and trig chart, for the most part, but I don't have the formulas down for the word problems and whatnot that was shown to us in class.

Getting back on track, lets talk about something simple, like converting degrees to radians and vice versa!

This is clearly one of the more simple, if not the simplest, thing we will be doing in this class all year. :'(

No one else should have trouble with this if I can understand it.

All you need to know are two easy little formulas. I'll start with Degrees to Radians, give an example and then do the same with Radians to Degrees.

Degrees to Radians = pi/180

Ex. Convert 72 degrees to radians.

Instead of plugging it into your calculator just put the function down on paper and solve by treating pi as a variable.

So you would proceed with 72/1 x pi/180

Multiply straight across 72 x pi
1 x 180

And your product comes out to be 72 pi/180

That reduces to 2 pi/5

And that is your answer, if you can't reduce in your head just plug the fraction into the calculator without the pi in the function.

On the Flip side!

If you need to convert Radians to Degrees you just use the reciprocal of the first formula.

Radians to Degrees = 180/ pi

Ex. Convert 4 pi/ 2 to degrees

You set up the equation 4 pi x 180
2 x pi

Now you can clearly see that you can cancel out the bottom half of the equation.

The pi's cancel out and since 180 is divisible by 2 it can be reduced.

You are then left with 4 x 90

Your answer is then 360 Degrees

That is it for tonight's lesson, I sincerely hope that it helped someone in some way.