Is x a scalar? If so, then you write it as x^2. Is x a vector? Then, assuming you want to perform an element-wise squaring, you use x.^2. If you are asking this question, you REALLY need to be reading the getting started tutorials - the Onramp tutorials are a good place to start. There are also multiple MATLAB tutoring sessions on Youtube to watch. Finally, when you get an error. then show what you did. Show the COMPLETE error message, thus everything in red. Otherwise we need to make wild guesses as to what you did wrong.

You almost got it. Since x is a vector, you should use elementwise operators. not x^2 (what's the square of a vector?) but x.^2.

Hi Christian, Try this: title(sprintf('Surface Ions per nm^2: %0.2f x 10^%i', 10^mod(log10(surfaceIons),1),floor(log10(surfaceIons))))

Hi Adomas Bazinys this is John BG What you want to do is, the way you want to do it, indeed good exercise, but 1. What about *fsolve* At Mathworks the function *fsolve* was time ago developed precisely so that the people using MATLAB could save time avoiding the need for any writing of such functions, and go straight to the roots, have a look: fun = @(x) exp(x)-3*x; x0 = [1.5,0]; x = fsolve(fun,x0) x = 1.512134551657842 0.619061283355628 2. Don't start with x0=[0 0] or [1 0] because then *fsolve* only returns a single real solution 3. The requested graph fplot(fun);grid on <> . 4. And the table x_range1=0;x_range2=10;xrange_step=1; x1=[x_range1:xrange_step:x_range2]';fx1=fun(x1); T1=table(x1,fx1) T1 = 11×2 table x1 fx1 __ __________________ 0 1 1 -0.281718171540954 2 1.38905609893065 3 11.0855369231877 4 42.5981500331442 5 133.413159102577 6 385.428793492735 7 1075.63315842846 8 2956.95798704173 9 8076.08392757538 10 21996.4657948067 I assumed you ask for a MATLAB table. You can also export this table to Excel, Word or a simple .txt file, if you choose to call those the intended tables to hold the result. 5. Checking the 4 limits +- Inf +-1j*Inf syms n;limit(exp(n)-3*n, n, -inf) = Inf syms n;limit(exp(n)-3*n, n, inf) = Inf syms n;limit(exp(1j*n)-3*1j*n, n, inf) = NaN syms n;limit(exp(1j*n)-3*1j*n, n, -inf) = NaN Do you really need considering exp(1j*imx)-3*1j*imx ? If so the start point is exp(1j*imx)-3*1j*imx = cos(imx)+1j*(sin(imx)-3*imx) this would be when real(x)>>imx=imag(x) 6. the 2 real roots found with *fsolve* probably turn into a corona of complex roots that may be appreciated developing a bit further the following start point. rangelim=15;rangestep=.01; rex=[-rangelim:rangestep:rangelim]; imx=[-rangelim:rangestep:rangelim]; [RX,IX]=meshgrid(rex,imx); Z=exp(RX+1j*IX)-3*(RX+1j*IX); figure(2);hs=surf(abs(Z),RX,IX);hs.EdgeColor='none'; Adomas If interested in the complex roots, please let me know. If you find the so far supplied answer useful, would you please be so kind to consider marking my answer as Accepted Answer? To any other reader, if you find this answer useful please consider clicking on the thumbs-up vote link thanks in advance John BG

you need to take a look at MATLAB syntax. Here is the equation you are trying to write: y = exp(0.5x)sin(2x) Here is what you actually wrote: y = exp(1)0.5x sin(2)x What you wrote was exponential to power of 1, times x halved, times sin of radians 2, times x. In MATLAB, to use the exponential function correctly you’d want exp(0.5.*x), same with the sin function: sin(2.*x) The command window is a great tool. Why not compare what exp(1) produces with exp(x)? Test everything to understand the syntax. Also use the documentation for any function. For example, for documentation of exp, type “help exp” or “doc exp”.

I=@(x) s(x).*sin(2*pi*f*x); plot(x,I(x)) Best wishes Torsten.

Hi, Richard. To evaluate f(x) at different values of x, you can create an .m file and write this code: function y = f(x) y = 2 * (x^3) + 7 * (x^2) + x; If you save the file under the name 'f.m', you can run the function by typing this code in the Command Window or a separate .m file. x = randi(7); y = f(x) The randi function above generates a 1-by-5 row vector of random integers between 1 and 10. The values returned by f are stored in a 1-by-5 row vector y. For more information about creating functions, see: http://www.mathworks.com/help/matlab/matlab_prog/create-functions-in-files.html. You can create a handle to the function f with an @ sign. For example, create a handle named myHandle as follows: myHandle = @f; Now you can run f indirectly by using its handle. y = myHandle(x) For more information about function handles, see: https://www.mathworks.com/help/matlab/matlab_prog/creating-a-function-handle.html.

You should start with the Matlab on-ramp and look for things in matlab’s built-in help browser. https://www.mathworks.com/help/matlab/getting-started-with-matlab.html ‘fplot’ is for plotting symbolic equations, which is a more advanced topic for Matlab, since it really is designed with arrays/matrices in mind. You are looking for ‘plot’. Info, including examples, here: https://www.mathworks.com/help/matlab/learn_matlab/plots.html After that, go line by line in your code and make sure it outputs what you think it should, and if there are errors, figure out what they mean and how to fix.