Program "Grapher" will not graph my equation. Please help?

[philmanwill]

So I am in AP Calculus and I need to graph something on the computer. Heres the pictures. First one is the overall program. My equation is highlighted in blue at the top of the screen. The second picture is the error message its giving me. Any ideas on whats going on here?

 

[MisterMe]

... Any ideas on whats going on here?

Parts of that bottom expression render it an invalid equation.

 

[mkrishnan]

I don't see anything overtly wrong with the equation. Y doesn't take on real values for many different values of X (e.g., x>4, as well as sufficiently large negative X's), and y is not a function of x (i.e., more than one y exists for a given x in some places), but that itself ought not be a big deal, and the program deals with those issues fine when you input the parts individually. Are you sure you entered in the multiple condition right side of the equation correctly?

 

[philmanwill]

Here's part of the more detailed report. Does this help? I am not actually in calc, but my girlfriend is and she is using my computer. Thanks everyone so much!

 

[philmanwill]

Here's what it SHOULD look like. But to get it, I had to spilt the equation and conditions over 2 different equations also shown on in the pictures. Any way i can take those 2 equations and combine them to one to form the same graph? thats the ultimate goal...

 

[Ganesha]

Here's what it SHOULD look like. But to get it, I had to spilt the equation and conditions over 2 different equations also shown on in the pictures. Any way i can take those 2 equations and combine them to one to form the same graph? thats the ultimate goal...

Are you sure it's suppose to look like that? What space are you supposed to be plotting this in?

Because y = sqrt(any real number) will never be a negative number.

 

[mkrishnan]

Because y = sqrt(any real number) will never be a negative number.

In this kind of math, the principal square root isn't usually being denoted by the radical... (-3)^2 = 9, etc...

But so your girlfriend's assignment is really to get the whole thing to display as a "single" equation in a graphing program? Isn't that a morose waste of time? I mean, this is something you can do with a pen and paper in two or three minutes and be over and done with it... nor does having a single representation in a computer program (when it can't be defined by a single formula at all values of X anyways, at least, not with a y=f(x) formulation) seems less than useful.

 

[iMacmatician]

This works, although it's not a function and you don't see the leftmost part of the graph due to resolution limitations.

 

[YB24]

Grapher equations

Another idea in attachment.
Don't forget the Inspector (resolution, 2 boxes to check)
So long, YB24

 

[YB24]

Grapher equations

Attachments forgotten. YB24

 

[MisterMe]

... Y doesn't take on real values for many different values of X (e.g., x>4, as well as sufficiently large negative X's), and y is not a function of x (i.e., more than one y exists for a given x in some places), but that itself ought not be a big deal, and the program deals with those issues fine when you input the parts individually. ...

You discovered the OP's error. Nothing in his expression limits his values of x to the domain –4 ≤ x ≤ 4. When Grapher tries a value of x outside the allowable domain, it blows-up.

 

[YB24]

Grapher

So I am in AP Calculus and I need to graph something on the computer. Heres the pictures. First one is the overall program. My equation is highlighted in blue at the top of the screen. The second picture is the error message its giving me. Any ideas on whats going on here?

At last ONE AND ONLY ONE EQUATION giving the FULL CURVE ! YB24