Question

Topic: MATLAB 101

Can someone help me with MATLAB ? I have 0.05% idea how this thing works. I'm just following instructions from the internet, but I'm still stuck with the problem below. Please anyone, teach me.

Answer 1

I already done with letter a. I used inline function on this question.

I have no idea how to do letter b. Can anyone help me out?

Answer 2

What have you learned so far?
Quadratic formula, Newton's method, fixed point iteration, Newton's for systems, or all of the above?

Answer 3

only quadratic formula i think :/
never heard of the other ones..

Answer 4

Is this a course on Matlab only, or it's a course on numerical methods/analysis using Matlab as a tool?

Answer 5

only matlab only

Answer 6

we are only focusing on the commands and stuff

Answer 7

Ok, then there's no expected method to solve the second.
For starters, here's an implicit plot of the system (second problem).
http://prntscr.com/8o3mfh

Answer 8

See if you can reproduce the same plot in Matlab (if you have covered graphics).

Answer 9

The solution near (2,3) is the top right intersection.

Answer 10

we are on the equations right now.. and
i got 2.4072 and 1.1106

Answer 11

if i'll use [2,3]

Answer 12

So you're in a class? I think you should pay attention to what the instructor is showing you instead!

Answer 13

no i have a vacant right now. This assignment is due on wednesday

Answer 14

(2.4,1.1) is definitely not the solution!

Answer 15

so my code is wrong >.<

Answer 16

Have you examined the graph and be convinced that (2.4, 1.1) is not the answer?

Answer 17

You can find out if you put your solution into the equations and see if f(x,y)=0, and g(x,y)=0.

Answer 18

Your solution works for g(x,y)=0 only. f(x,y) gives -36.0

Answer 19

So what method of solution of polynomial equations have you learned so far?

Answer 20

Not sure if you have included both equations into the 'eqns' parameter of fsolve.
That may be your only problem.

Answer 21

oh yeah i made x= x(1) and y=x(2)

Answer 22

You have missed out the 0 at the end of definition of F(1), which makes the constant 4 instead of 40. That's why when substituted you will get -36!
I think that's all you have to correct!

Answer 23

oh so now i get 2.696 and 3.3655 ?

Answer 24

I get 2.6963 and 3.3655 using just display(x).

Answer 25

yes! so those are right?

Answer 26

Absolutely.
If you need more digits, use a more elaborate version of print.

Answer 27

ahh okay. thank you so much!
finally, i can move on with the other exercise xD

Answer 28

Good! You're welcome! :)