Solving trig equation with TI Ispire CX

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The discussion focuses on solving the equation xsin(x) - cos(x) = 0 within the interval (0, 4) using a TI-Nspire CX calculator. Users initially struggle with the calculator's input, receiving an unsatisfactory output instead of solutions. A key point raised is the importance of correctly inputting the sine function as x·sin(x) rather than xsin(x) to ensure the calculator recognizes it properly. After correcting the input, one user confirms that they successfully obtained the correct solution. The thread emphasizes the need for precise syntax in calculator operations to achieve accurate results.
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Homework Statement


solve xsin(x)-cos(x)=0 on interval (0,4) using the calculator

Homework Equations


xsin(x)-cos(x)=0

The Attempt at a Solution


I have tried working the problem out through first pressing menu- 3 (algebra)- 1 (solve)- inserting the equation- inserting the interval.
However, when I press the enter button, I get this equation instead of solid solution(s).
Below is my work on the graphing calculator.
1515317466681.jpg

 

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Sunwoo Bae said:

Homework Statement


solve xsin(x)-cos(x)=0 on interval (0,4) using the calculator

Homework Equations


xsin(x)-cos(x)=0

The Attempt at a Solution


I have tried working the problem out through first pressing menu- 3 (algebra)- 1 (solve)- inserting the equation- inserting the interval.
However, when I press the enter button, I get this equation instead of solid solution(s).
Below is my work on the graphing calculator.
View attachment 218028
Can't you simply graph that ?
 
Sunwoo Bae said:

Homework Statement


solve xsin(x)-cos(x)=0 on interval (0,4) using the calculator

Homework Equations


xsin(x)-cos(x)=0

The Attempt at a Solution


I have tried working the problem out through first pressing menu- 3 (algebra)- 1 (solve)- inserting the equation- inserting the interval.
However, when I press the enter button, I get this equation instead of solid solution(s).
Below is my work on the graphing calculator.
View attachment 218028
You're missing a couple of steps. Here's a quick tutorial on how to do that exact kind of problem analytically (as opposed to graphically) on the N-Spire.
 
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ComplexVar89 said:
You're missing a couple of steps. Here's a quick tutorial on how to do that exact kind of problem analytically (as opposed to graphically) on the N-Spire.

I tried the exact steps, and the solution turns out the same way.
1515370239689.jpg
I don't know why, but it works on ti 84
1515370241050.jpg
 

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Last edited:
SammyS said:
Can't you simply graph that ?
yes but i want to know how to do it without graphing it!
 
Sunwoo Bae said:
yes but i want to know how to do it without graphing it!
It looks like you have ##\ xsin(x)\ ## rather than ##\ x\cdot\sin(x) \ ##.

So it's not treating ##\ sin\ ## as a function.
 
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SammyS said:
It looks like you have ##\ xsin(x)\ ## rather than ##\ x\cdot\sin(x) \ ##.

So it's not treating ##\ sin\ ## as a function.
thanks it worked!
 
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