Anonymous

# 10 pts for anyone who's a graphing calculator guru! How do you graph PARAMETRIC equations?

say, x= t^2-2

Do you set it to "PAR" mode? If so, does it matter if I put it after X1T or Y1T?

Update:

I didn't know they had to go together...

the other one was y=3t or

Relevance

In parametric equations, x and y move independent of each other. This allows them to cross, loop, and do other kinds of "crazy" things that they wouldn't do with functions.

Recall that functions only have one output y for every input x, meaning they don't circle or loop or curve backwards onto themselves.

A parametric function on the other hand has an equation for each of the variables, for example:

x = t² - 2

y = 3·t

This means that while the x-values follow a parabolic path (coming the left and then curving and going back left), the y-values will follow a linear path. The value t connects them together and determines how fast these operations are done relative to each other. If you changed the y part to 2·t, then the y would not increase as quickly as x formed a parabola, which would crease a "slimmer" right-opening parabola.

So, to answer your question, it definitely does matter what order you put them in and you need both (or it isn't a parametric equation at all).

• It most certainly does matter whther you put the equation after the x1 or the y1...is x=t^2-2 a parametric equation? It doesn't look like it unless you put a y=some y(t) after the x(t), then you would have a complete set of parametric equations.

• you want to sparkling up those 2 equations for y and then plug it in. operating example the 2d one may be: y=x²+x+a million the different is slightly trickier yet not that perplexing to do with a pencil and paper.