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Math function

ACOTH

Returns the inverse hyperbolic cotangent of a number.

Rarely usedDifficulty 1400 · AdvancedUsage rank #334 of 520
Practice · 2 questions →

When to use it

Inverse hyperbolic cotangent. Defined for inputs with absolute value greater than 1.

The shape of it

Syntax
=ACOTH(number)

Worked examples

  • Six

    =ACOTH(6) 0.168236118

    Half of LN(7/5).

  • Two

    =ACOTH(2) 0.549306144

    Half of LN(3).

  • Negative

    =ACOTH(-3) -0.34657359

    Odd function: negative in, negative out.

Worth knowing

  • ACOTH(x) = 0.5*LN((x+1)/(x-1)).
  • COTH inverts it.
  • Mostly seen in physics and signal work.

Where it goes wrong

  • #NUM! when the absolute value of the input is 1 or less.
  • Returns a plain number, not an angle.

Related

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