Can 4/3(sin theta) = theta be algebraically solved?

  • Thread starter choob
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In summary, the conversation is discussing the solution to the equation 4/3(sin theta)=theta, specifically in the context of an exam question. It is mentioned that there is no algebraic solution and the best method is to use a graphing calculator or computer to find an approximate solution. The possibility of using Maclaurin's series and Newton-Raphson iterative method is also mentioned.
  • #1
choob
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those above steps imo are unnecessary, all i need to know is how to solve 4/3(sin theta)=theta, thanks in advance!
 
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  • #2


Two things:
  1. Is your equation 4/3 * sin(theta) = theta or is it 4/[3 sin(theta)] = theta?
  2. You are not going to be able to solve your equation, whichever one it is, by algebraic means. The best you can do is to get an approximate solution.
 
  • #4


The link you gave is broken, so I don't know what you meant to show me. In any case, what I said in post 2 still applies.
 
  • #5


its not broken, all you have to do is click on the address bar and press enter, as if you were typing the url in.
 
  • #6


Mark44 said:
The link you gave is broken, so I don't know what you meant to show me. In any case, what I said in post 2 still applies.
choob is actually right, you have to do something like copying and pasting the URL instead of just following the link. The site is probably trying to prevent direct linking.

Anyway, the PDF file doesn't change anything - there is no analytic solution. You would need to use a graphing calculator or a computer to find the answer. (There's probably some sort of series expansion trick or something you could use to get a good approximation by hand)
 
  • #7


If it's 4/3 * sin(theta) = theta you can find one pretty obvious solution.
 
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  • #8


freeexampapers has had a lot of bandwidth problems. We welcome direct linking and plan to have enough bandwidth to allow this.
 
  • #9


Cyosis said:
If it's 4/3 * sin(theta) = theta you can find one pretty obvious solution.

Hi Cyosis ! I took some time looking and pondering of the possible solution and i could not figure it out , I hope you can provide me of the partial solution. Thank you.
 
  • #10


Can somebody explain what's the task?
 
  • #11


Дьявол said:
Can somebody explain what's the task?

solve for theta
 
  • #12


i tried using maclaurin's series and i manage to work out with the answer of 1.28 but i guess it is rather tedious.
 
  • #13


icystrike said:
i tried using maclaurin's series and i manage to work out with the answer of 1.28 but i guess it is rather tedious.

Well you could use the Newton-Raphson iterative method and find an approximation.
 
  • #14


rock.freak667 said:
Well you could use the Newton-Raphson iterative method and find an approximation.

Yes indeed Newton Raphson method can solve and it is similar to taylor'series.
Is there any other method to solve this question algebraically?
 
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  • #15


No.
Yes, I was also quite dissappointed to hear that such a simple result such as the one you have presented has no means of being algebraically solved; but what can you do...
 

FAQ: Can 4/3(sin theta) = theta be algebraically solved?

What is the general approach for solving 4/3 sin(x) = x?

The general approach for solving this equation is to use algebraic manipulation and the unit circle to find the solutions for x.

How do I use the unit circle to solve this equation?

The unit circle is a circle with a radius of 1, centered at the origin on the coordinate plane. It can be used to find the values of sine and cosine for any angle. By setting 4/3 sin(x) equal to x and simplifying, we can find the values of x that correspond to the points where 4/3 sin(x) and x intersect on the unit circle.

Are there any restrictions on the values of x that satisfy this equation?

Yes, there are restrictions on the values of x. Since the sine function has a range of -1 to 1, the values of x must also fall within this range in order to satisfy the equation. Additionally, since the sine function is periodic, there will be an infinite number of solutions for x.

Can I use a calculator to solve this equation?

Yes, you can use a calculator to solve this equation. However, it is important to understand the concepts behind solving the equation in order to use the calculator effectively. Also, keep in mind that calculators often give approximate solutions and may not show all possible solutions.

How do I check my solutions for this equation?

To check your solutions, plug them back into the original equation and see if they satisfy the equation. You can also graph both sides of the equation and see if they intersect at the given x values. Additionally, you can use a calculator to evaluate both sides of the equation and see if they give the same value.

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