Hi Cristiene,

First, a couple of suggestions:

If you open the Help system in Mathematica and search for "Virtual Book" you will find a very nice introduction to Mathematica. It is really worth spending some time with it.

Also, if you have trouble with a built-in function, highlight it and press F1. The Help will go right to it.

But there are a lot of helpful people here in the community as well, and they all love Mathematica. The best thing is to read How to Post. This will tell you how to post your code in a code block or attach notebooks so people who want to reply can cut and paste your code into Mathematica to try it.

Concerning your plot:

f[x_] := x Cos[1/x]

Plot[f[x], {x, 0, Pi}]

Notice that both Cos and Plot are capitalized. Mathematica is case sensitive, and all built-in functions are capitalized. Your symbols and functions should begin with lower case, to avoid conflict.

Best regards, David

PS: I see now some earlier responses which I duplicated. The dashboard and forum on my laptop is approximately 1 hour behind the forum as viewed on my IPad. I suspect Relativistic effects. I will try to adjust their relative velocities.

(NEED HELP recently downloaded the software)

Answer in another pod.

Thank you for replying back so for example the question is solve the following equation using the solve command and check your answer with a plot (a) x^2+3x+1=0

I put :

Solve[x^2 + 3 x + 1 == 0]

it gave me that :

{{x -> 1/2 (-3 - Sqrt[5])}, {x -> 1/2 (-3 + Sqrt[5])}}

when I tried to plot :

plot[function[x, x^2 + 3 x + 1][x]]

it gave me :

plot[function[x, 1 + 3 x + x^2][x]]

which is the same what I wrote so what did I do wrong ?

Hi,

it will be very difficult to help you. There is no real question in your post to answer. You just state that you are having problems and that you need help. Unless you are much more specific about your problem(s) people here will have a hard time helping you.

Cheers, Marco