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+--- Thread: Integral in solve (/thread-1824.html)
Integral in solve - lrdheat - 07-13-2014 06:05 PM
How would I set up an integral in solve app to, say, have integral x^2 from 0 to y = 20?
RE: Integral in solve - Joe Horn - 07-14-2014 08:17 AM
(07-13-2014 06:05 PM)lrdheat Wrote: How would I set up an integral in solve app to, say, have integral x^2 from 0 to y = 20?
Do you mean \(\int_0^{20}x^{2} dx\) ? That's not an equation, it's just an expression. To evaluate an expression, just type it into Home or CAS; this one evaluates to 8000/3. The Solve app is for solving equations.
If I misunderstood your question, what equation you want to solve?
RE: Integral in solve - eried - 07-14-2014 08:38 AM
(07-14-2014 08:17 AM)Joe Horn Wrote:(07-13-2014 06:05 PM)lrdheat Wrote: How would I set up an integral in solve app to, say, have integral x^2 from 0 to y = 20?
Do you mean \(\int_0^{20}x^{2} dx\) ? That's not an equation, it's just an expression. To evaluate an expression, just type it into Home or CAS; this one evaluates to 8000/3. The Solve app is for solving equations.
If I misunderstood your question, what equation you want to solve?
He says equals to 20, so it is an equation. Not solvable in the solver.
RE: Integral in solve - CR Haeger - 07-14-2014 12:44 PM
(07-13-2014 06:05 PM)lrdheat Wrote: How would I set up an integral in solve app to, say, have integral x^2 from 0 to y = 20?
In Solve App this seems to work okay (using Home variables X, T and the math template):
[attachment=959]
In CAS, you can use solve(), fsolve() to get a numerical or symbolic result
[attachment=960]
RE: Integral in solve - Tim Wessman - 07-14-2014 04:37 PM
(07-13-2014 06:05 PM)lrdheat Wrote: How would I set up an integral in solve app to, say, have integral x^2 from 0 to y = 20?
This works fine. However, if you tried this and it didn't work, it is probably because you accidentally did x^2d(x=20) instead of (x^2)dx =20
Make sure you press the right arrow once after to move out of the variable of integration template location before your =20.
RE: Integral in solve - Anderson Costa - 07-14-2014 09:57 PM
(07-13-2014 06:05 PM)lrdheat Wrote: How would I set up an integral in solve app to, say, have integral x^2 from 0 to y = 20?
It may be expressed for int(x^2,x,0,y)=20...
It's an Integral equation and is easily solved in Solve App!
RE: Integral in solve - lrdheat - 07-15-2014 02:09 AM
I've tried the syntax (and other variations) suggested by Anderson, Tim, and CR. In each case, when I go into Num template and submit a guess, I get "bad guess(es)". Could I be in an odd operating mode?
RE: Integral in solve - eried - 07-15-2014 02:48 AM
(07-15-2014 02:09 AM)lrdheat Wrote: I've tried the syntax (and other variations) suggested by Anderson, Tim, and CR. In each case, when I go into Num template and submit a guess, I get "bad guess(es)". Could I be in an odd operating mode?
I get the same :/ that's why I said it was not solvable in that app. I tried with int and with the template too.
RE: Integral in solve - Joe Horn - 07-15-2014 06:09 AM
(07-15-2014 02:48 AM)eried Wrote:(07-15-2014 02:09 AM)lrdheat Wrote: I've tried the syntax (and other variations) suggested by Anderson, Tim, and CR. In each case, when I go into Num template and submit a guess, I get "bad guess(es)". Could I be in an odd operating mode?
I get the same :/ that's why I said it was not solvable in that app. I tried with int and with the template too.
See Tim's reply above. If you're using Textbook Entry mode, you have to press right-cursor between typing dX and typing =20.