Difference between arctan(x) and cot(x)

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Arctan(x) is the inverse function of tan(x), meaning if tan(x) = y, then arctan(y) = x. Cotangent, defined as cot(x) = 1/tan(x), is not equivalent to arctan(x). The notation tan^-1(x) refers specifically to the inverse function, not the multiplicative inverse. Therefore, arctan(x) does not equal cot(x). Understanding these distinctions clarifies the relationship between these trigonometric functions.
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If arctan(x) = tan(x)^-1 and since tan(x) = sin(x)/cos(x) is not arctan(x) = cot(x). I know something's not right here but what is it?

Thanks.
 
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No no.
Cot(x)=1/tan(x)

arctan(x)=tan-1(x) \neq1/tan(x)
 
rock.freak667 said:
No no.
Cot(x)=1/tan(x)

arctan(x)=tan-1(x) \neq1/tan(x)

Just to clarify, that notation doesn't mean the multiplicative inverse in this context, but the inverse function.

tan(x)=y
Arctan(y)=x
With whatever restrictions are necessary so that those are functions and not just relations.
 
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