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Topic review (newest first)
- bobbym
- 2012-05-01 19:49:17
Take what amberzak is doing in the other threads. Geogebra does those in under a minute!
- anonimnystefy
- 2012-05-01 19:44:58
I agree. Geogebra has many cool and useful functions for something that is generally thought of as a graphing software.
- bobbym
- 2012-05-01 19:40:47
I did not say you can not get it, but the thinking has already been done for us
in Geogebra.
- anonimnystefy
- 2012-05-01 19:38:07
Why not just enter the difference of the two functions?
- bobbym
- 2012-05-01 19:37:20
That does not get the integral between two curves. Geogebra does that for us, M does not.
- anonimnystefy
- 2012-05-01 19:36:14
Integrate[f(x),{x,a,b}] ?
- bobbym
- 2012-05-01 19:31:28
Yep, M has nothing like it.
- anonimnystefy
- 2012-05-01 19:29:43
Do you mean the integral function?
- bobbym
- 2012-05-01 08:58:18
Did you read post #2?
- anonimnystefy
- 2012-05-01 08:34:32
How so?
- bobbym
- 2012-05-01 08:33:08
For this type of problem, Geogebra is more powerful than M.
- anonimnystefy
- 2012-05-01 08:30:06
Ok then.
I am thinking about making another one of these.
- bobbym
- 2012-05-01 08:26:47
Yes, I left that for the readers to get.
- anonimnystefy
- 2012-05-01 08:07:07
Hi bobbym
Why don't you zoom in? That way you have "more" space to put more points. I think you can get a 100 even.
- bobbym
- 2012-05-01 07:30:00
Hi;
Another one came up. We need the area of the red shape in the first picture.
1) Input f(x) = x+1. A straight line will be drawn.
2) Input g(x)=6x-x^2-3. A parabola will be drawn.
3) Get the points of intersection of the two equations using the intersection tool. The points will be labelled A,B.
4) Go into options, labelling and check no new objects. Also hide the labels of A and B.
5) Use the polygon tool and carefully click on A and then place as many points as you on that curve until you finish at B and then click A to complete the polygon. I managed 19 points on the curve. See the second picture.
6) Read off the value of poly1, I got 4.48347. That is a good estimate of the area of the red area.
Now geogebra has an incredible command that does this for us.
7) Input integral[f,g,x(A),x(B)] and immediately our area is hsaded darker and in the algebra pane you will see a new value of 4.5. That is the exact answer. I am quite close. How did you do?