Why is it impossible to solve y explicitly in this equation?

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The equation y + sin(y) = x cannot be solved explicitly for y due to the transcendental nature of the sine function, which complicates algebraic solutions. To graph this function, one approach is to create a table of values by selecting y-values and calculating corresponding x-values. While a closed-form solution is not available, numerical methods can be used to find solutions within certain bounds. The discussion also mentions the possibility of graphing x as a function of y and then flipping the axes for visualization. Ultimately, the challenge lies in the inherent complexity of the equation caused by the sine function.
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$$y+siny=x$$

How would you even graph a function like this if you can't solve for y explicitly?
 
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InvalidID said:
$$y+siny=x$$

How would you even graph a function like this if you can't solve for y explicitly?
Make a table of values. Pick some y-values and solve each of them for x.
 
Why is it impossible to solve y explicitly in this equation?
 
The presence of sin y. Trig functions are transcendental and cannot be solved using algebraic methods alone.
 
SteamKing said:
The presence of sin y. Trig functions are transcendental and cannot be solved using algebraic methods alone.

With this in mind (and I agree) one cannot solve this either,
\sin{y} = x
We have to invent a special function, the inverse sine, to solve it. By that same logic, we can invent a special function to solve the original equation. But it would be no more "solved" than using the inverse sine function to solve my equation above.
 
you can graph x as a function of y explicitly, then turn the graph by 90° and flip (mirror image) the rotated graph.

i do not think there is a closed form solution to

y + a \sin(y) = x

but you can still solve it numerically, as long as |a| \le 1. there are places in the y=f(x) function where the slope is infinite, but only on a single point. sort of like the real function y = x^{1/3}.
 
Have you tried to apply the explicit function theorem to see if a local solution for y is
possible?
 
InvalidID said:
$$y+siny=x$$

How would you even graph a function like this if you can't solve for y explicitly?
Graph y= x+ sin(x), then flip the x and y axes.
 
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