# how to write a function in interval?

40 views (last 30 days)
lina on 21 Oct 2014
Answered: Rupa Kupireddy on 8 Feb 2022
hi,
can you please help me to write this function code in matlab?
thank you in advance
##### 2 CommentsShowHide 1 older comment
lina on 21 Oct 2014
I attached the question in jpg form can't write the code :'(

Matt Tearle on 21 Oct 2014
MATLAB Academy can help you learn the basics of MATLAB. Also the Getting Started section of the doc, as Jose-Luis suggested.
For this specific question, you'll need to:
1. create a vector of x values from -2 to 5.
2. create a corresponding vector of y values by evaluating the function.
3. plot y as a function of x.
4. maybe pretty up the graph a bit.
For 2 you'll need to know about array operations. For 4 you can use xlabel, ylabel, title, xlim, ylim, and/or axis.
As Jose-Luis mentioned, if you need the roots exactly, you can use fzero, but that seems a bit advanced for HW#1. Because the function is a polynomial, you could also use polyval (for part 2) and roots. But, again, that seems more than is necessary.
Matt Tearle on 22 Oct 2014
You don't need to specify the domain to the plot function, just the x values and their corresponding y values (in that order): plot(x,y)
If you want to adjust the axis limits that MATLAB chooses, use the xlim and/or ylim functions (use the doc to see how they work).

### More Answers (1)

Rupa Kupireddy on 8 Feb 2022