an question need to solve

Many applications use the following “small angle” approximation for the sine to obtain a simpler model that is easy to understand and analyze. This approximation states that sin x ≈ x, where x must be in radians. Investigate the accuracy of this approximation by creating three plots. For the first, plot sin x and x versus x for 0 ≤ x ≤ 1. For the second, plot the approximation error sin x - x versus x for 0 ≤ x ≤ 1. For the third, plot the relative error [sin(x) - x]/sin(x) versus x for 0 ≤ x ≤ 1. How small must x be for the approximation to be accurate within 5 percent?

[the cyclist]

Please read this guide about getting help with homework, and edit your question accordingly.

[Mahmoud Ibrahim]

The topic is not like that. I have a solution to the question, but I do not understand the code

[Mahmoud Ibrahim]

this is the solution but why we used abs here in second plot and multi 100 in the third plot @the cyclist

The m-file:

x = 0:0.01:1;

subplot(2,2,1)

plot(x,sin(x),x,x)

xlabel('x (radians)'),ylabel('x and sin(x)')

gtext('x'),gtext('sin(x)')

subplot(2,2,2)

plot(x,abs(sin(x)-x))

xlabel('x (radians)'),ylabel('Error: sin(x) - x')

subplot(2,2,3)

plot(x,abs(100*(sin(x)-x))./sin(x))

xlabel('x (radians)'),... ylabel('Percent Error'),grid

[the cyclist]

Yes, I see that this solution appears on the Chegg web site.

My hypothesis is that you found this solution to your homework on the web, and you don't understand it.

I will give you a couple small hints, under the assumption that you would still like to learn.

Hint #1 (about using abs): If you are making an error, do you care what direction the error is in?

Hint #2 (about multiplying by 100): Think about what percent error means.

[Mahmoud Ibrahim]

@the cyclist Bro i do not have an acc on this chegg site.

It is not homework

i just want to understand because i have an exam tomorrow and i solve many example to be ready

[Steven Lord]

The information on this Wikipedia page may help you understand the use of abs and why the code multiplies by 100.

Answer 1

[Image Analyst]

This looks like a homework problem. If you have any questions ask your instructor or read the link below to get started:

How do I get help on homework questions on MATLAB Answers? - MATLAB Answers - MATLAB Central

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