Limit of sin(x<sup>0</sup>)/x as x→0 = π/180

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Discussion Overview

The discussion revolves around the limit of the expression (sin(x0)/x) as x approaches zero, with a specific claim that this limit equals π/180. Participants explore the notation and meaning behind the expression, including the implications of using degrees versus radians.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • One participant asserts that the limit of (sin(x0)/x) as x approaches zero is π/180, seeking a proof for this claim.
  • Another participant criticizes the initial notation as confusing and suggests that it lacks mathematical meaning, implying that the sine function should be interpreted in radians.
  • A participant clarifies that "sin(x0)" refers to sine of x raised to the power of zero, which equals 1, leading to the limit of 1/x as x approaches zero, which does not converge to π/180.
  • Some participants discuss the interpretation of x as being in degrees, suggesting that this changes the limit calculation and leads to a different expression involving radians.
  • One participant presents a numerical approach to demonstrate that as x approaches zero, sin(x)/x approaches 1, arguing against the original claim of π/180.
  • Another participant emphasizes that the numerical evidence presented does not conclusively prove the limit, as it could be misleading without proper context.

Areas of Agreement / Disagreement

Participants express disagreement regarding the interpretation of the limit and the notation used. There is no consensus on whether the limit equals π/180, as multiple interpretations and approaches are presented.

Contextual Notes

Participants highlight potential confusion arising from notation and the distinction between degrees and radians, which affects the limit's evaluation. The discussion includes unresolved mathematical steps and differing interpretations of the expression.

chandubaba
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prove that limit of (sin (x^0)/x) as x tends to zero is π/180(ie pi by 180)
 
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DO pay attention to what you are writing! Or are you comatose, perhaps??

What you've written is utterly meaningless.

If you want to say to a friend: "I really like you", do you say to him "bungafloop-floop"??

That's basically what you've written above in the mathematical language.
Is it really that difficult for you to form a proper sequence of mathematical symbols?


I assume you are talking about the sine function, where the argument is given in degrees, rather than radians, but that does not excuse your cavalier attitude with respect to notation.
 
by sin x^0/x ,i mean sine x to the power 0 divided by x .i have been using this notation for visual basic.sorry!
 
Last edited:
Now it's even more confusing than before!
I wasn't aware that visual basic allowed such sloppy, anti-mathematical notation. "sine x to the power 0" is (sin x)^0, not sin x^0 which means "sin of (x^0)= sin(1)". In any case, (sin x)^0= 1 so you are really asking about 1/x as x goes to 0. Of course, that does not converge at all, certainly not to \pi/180

If you meant, by x^0, "x written in degrees", as arildno suggested, then, since the value "in radians" would be \pi x/180 your sin(x)/x becomes sin(\pi x/180)/x You could multiply both numerator and denominator of that by \pi /180 and let y= \pi x/ 180 to get
\frac{\pi}{180}\frac{sin y}{y}
which does have the limit you ask for.
 
Remember that the degree-circle is NOT a power!
The degree-circle works in a similar manner as "m" for "meters":

2m means "two meters".
 
chandubaba said:
prove that limit of (sin (x^0)/x) as x tends to zero is π/180(ie pi by 180)
I agree with arild.

Now, there are several ways to "prove" limits, but in this case it is simply easier to use the definition of limits: "As the function of X approaches a singular point from the left and the right, the limit is the point that they are coming close to."

Therefore, we can plot out the point and come to the point it is coming close to. In this case, here's our information:

f(x) = sin(x)/x

We're looking for:

Lim(x->0)[sin(x)/x] = ??

Well, create a chart proof:

From right to left:
x: y:
.1 .998334
.01 .999983
.001 .999999
0 undef
-.001 .999999
-.01 .999983
-.1 .998334

The function as X is approaching 0 is 1. Therefere by the definition of limits:

Lim(x->0)[sin(x)/x] = 1

Q.E.D.
 
No, it isn't GoldPhoenix.
Most probably, OP is given x as measured in DEGREES, rather than in radians.
Check your calculator again.
 
I would also point out that the fact that
1 .998334
.01 .999983
.001 .999999
0 undef
-.001 .999999
-.01 .999983
-.1 .998334

looks like it is getting close to 1 proves absolutely nothing about the limit. It would be very easy to make up functions that have exactly those values but are, say, -1000000 for x <b>close</b> to 0 ("close" here meaning "less than 0.00000000001 from 0".
 

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