Trigonometry Help!!!

[MagicCarpetRide]

Not sure I spelled that right but my Pre-cal grade is depending on this worksheet that I don't know how to do.
I have to graph
r=-sin(x)
I used x to replace theta because I don't know how to do that on a computer.
Anyway I'm supposed to graph this on a circle and include a table of values. I don't understand anything so please if someone could just get me started. This is due in a couple of hours.

[lxDestinyxl]

Re: Trigonometry Help!!!

Wrong section of the forums, buddy.
Next time, post in THIS part of the forums.

For Future reference, you can find this page through Critical Thinking > Homework & General Information Forum.

Just to let you know, I ever-so-highly advice you to read THIS before you post any threads.

Have a good day, and make sure to listen in class,
Destiny.

[MagicCarpetRide]

Re: Trigonometry Help!!!

oh wow, sorry. I didn't think there was a section for that.
If someone could move this or something that would be nice, or help that would be nicer.

[Commandersa1]

Re: Trigonometry Help!!!

You would have to rename your thread like, [High School - Pre-Calculus] Graphing Sin.

, but to help you. Are you suppose to graph -sin(x), and a circle? Like sqrt(16-x^2) for y1, and -sin(x) for y2. I hope that is what you meant.

[MagicCarpetRide]

Re: Trigonometry Help!!!

Well I need to start by changing r=-sin(x) to polar coordinates or something. Maybe rectangular coordinates. That's the thing I don't know any of this. And it's not actually x it is the symbol for an angle but I can't type that so I'm replacing it with x for now.

[bluguerrilla]

Re: Trigonometry Help!!!

So in polar coordinates 'r' is the length out from the center of the graph and 'theta' is the angle from the line going to the right from the center, up.



Sin(q) you know in cartesean coordinates starts at 0, goes up to 1, back down to zero, to -1 and then to zero again after going 360 degrees (or 2pi radians). To plot -Sin(x) just multiply all those numbers by -1.

So, plot those points in polar coordinates and connect the dots.

Edit: Also, if you have a calculator (TI-83 or something) just go into Mode and change the Graphing option from Rect to Polar.

Edit2: Or, http://fooplot.com/ but don't just copy down, if you don't understand any of this, I can elaborate.

[MagicCarpetRide]

Re: Trigonometry Help!!!

Thank you. I actually can understand that but my teacher requires a chart of values or something so I guess my chart should be like.... R on the left and theta on the right.......?

I got the graph by using my calculator haha but I don't know how to do that chart. That might not be what I want for x y like.

[bluguerrilla]

Re: Trigonometry Help!!!

Sounds like she probably does want a chart of r and theta.

I'd do it in 30 degree increments.

[Tasselfoot]

Re: Trigonometry Help!!!

looks like blu pretty much helped you with all you need... so, won't bother moving this. just a lock.