12-19-2014, 04:55 PM
Post: #1
 lrdheat Senior Member Posts: 542 Joined: Feb 2014
Another graphing area question...how would I plot area in advanced plot app of MAX(SIN(X),COS(X)) ?
12-19-2014, 05:28 PM (This post was last modified: 12-19-2014 05:31 PM by Snorre.)
Post: #2
 Snorre Member Posts: 101 Joined: Dec 2013
Hello,

I'd say you should do it with the "Function" app by plotting F1(X)= "MAX(SIN(X),COS(X))".
But maybe you're more interested in the "Advanced Graphing" of V1: "SIN(X)>COS(Y)" and V2: "SIN(X)<COS(Y)".
It depends on what your intention is.

Greetings
12-19-2014, 05:38 PM (This post was last modified: 12-19-2014 06:25 PM by Han.)
Post: #3
 Han Senior Member Posts: 1,810 Joined: Dec 2013
Did you mean to shade in the area between the x-axis and the function max(cos(x),sin(x))? If so, then define F1 as MAX(SIN(X),COS(X)) and then in the advanced graphing app use:

V1: Y $$\ge$$ F1(X) AND Y$$\le$$ 0
V2: Y $$\le$$ F1(X) AND Y $$\ge$$ 0

Edit: If you want them to be of the same color (say using V1's color), then do:

V2(COLOR):=V1(COLOR);

Graph 3D | QPI | SolveSys
12-19-2014, 09:08 PM
Post: #4
 lrdheat Senior Member Posts: 542 Joined: Feb 2014
Hi Han,

I wanted to get the area under MAX(SIN(X),COS(X)) in the advanced function graphing app so that I could go to table and easily find "X" values that produce specified areas. This can be accomplished in the regular function app by subtracting a specific value for area using AREA(MAX(SIN(X),COS(X))-"specific area", and using function analysis to find root.

I wanted to have an easier way to query "x" values for a variety of specific areas by creating a table from the advanced graphing app.
12-19-2014, 10:51 PM (This post was last modified: 12-19-2014 11:00 PM by Snorre.)
Post: #5
 Snorre Member Posts: 101 Joined: Dec 2013

Am I right, that you want for any arbitrary area a to find an x(a), so that
$a=\int_0^x \max(\sin\theta,\cos\theta)d\theta$

If so, I haven't found a solution you might want, since I couldn't get "Advanced Graphing" to plot anything involving areas/integrals.

You could plot that in "Function" app (patience!), and then look at the numeric table. But this is driven by the step of x, not a(x).

Another way is using the "Solver" app.
1st: enter your problem; 2nd: solve x for a given a; 3rd: plot

Sorry, that's not the nice tabular solution (a vs. x(a)) you may expect
 « Next Oldest | Next Newest »

User(s) browsing this thread: 1 Guest(s)