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## Homework Statement

Two forces P and Q are applied at the end of a screw eye in order to remove the post.

## Homework Equations

The two equations that were found are

1.) Q*sin(30)-P*sin(θ)=0

2.) Q*cos(30)+P*cos(θ)-800=0

## The Attempt at a Solution

I combined the 2 equations by first solving (1) in terms of Q=2*P*sin(θ)

then plugged into equation (2) (2*P*sin(θ))*cos(30)+P*cos(θ)-800=0

then got f(θ)=sin(θ)*(√3)*P+P*cos(θ)-800=0

wanted f(θ)=0 as final equation

f'(θ)=P*(2*cos(30)*cos(θ)-sin(θ) (i do not think this is correct though)

Then I have to write a newton raphson for θ for a given P and solve for θ.

use P=400 to 800 with ΔP=25.

compute θ for each P

once θ is found for each P use equation (1) to find Q

Now plot P and Q for each θ.

I am very new to Matlab. (only introduced to it 2 weeks ago) and i am not to sure how to start. This is what i came up with but it is very confusing to me.

x0=400; n=16; eps=0.001; fun=@(tha) 2*p*sin(tha)*cos(30)+p*cos(tha)-800=0; fund=@(x) p*(2*cos(30)*cos(x)-sin(x); nr=(x0,n,eps,fun,fund)

function nr(x0, n, eps, f, fd)

func=f(x0); dfunc=fd(x0);

for i=400:n

x=x0-func/dfunc;

fprintf ('%4d %8.4f %8.4f %8.4f\n',i,func, dfunc, x)

func=f(x); dfunc=fd(x);

if abs(x-x0) < eps , break, end

x0=x;

end

**i know there needs to be an M-File for this set up but i am not sure how to do that either.

Thanks in advance for the help