For years, students of mathematics have recalled the trigonometric ratios by remembering the Great Chief SOHCAHTOA.

Each letter of the Chief's name represents the name of one of the trig ratios or the name of a side of a right triangle.

  • Sine of an angle = Opposite side / Hypotenuse
  • Cosine of an angle = Adjacent side / Hypotenuse
  • Tangent of an angle = Opposite side / Adjacent side
Here are some mnemonics for recalling the trig ratios:

  • Some Of Her Children Are Having Trouble Over Algebra.
  • Some Out-Houses Can Actually Have Totally Odorless Aromas.
  • She Offered Her Cat A Heaping Teaspoon Of Acid.
  • Soaring Over Haiti, Courageous Amelia Hit The Ocean And ...
  • Tom's Old Aunt
    Sat On Her
    Chair And Hollered.
    -- (from Ann Azevedo)

  • Stamp Out Homework Carefully, As Having Teachers Omit Assignments.
  • Some Old Horse Caught Another Horse Taking Oats Away.
  • Some Old Hippie Chasing Another Hippie Tripping On Apples.
  • School! Oh How Can Anyone Have Trouble Over Academics?
  • Oh Heck! Another Hour Of Algebra with Some Crazy Teacher.
  • Two Old Angels
    Skipped Over Heaven
    Carrying Ancient Harps

  • Two Old Angels
    Skipped Over Heaven
    Carrying A Harp

  • Oscar Had A Heap Of Apples
    - you just have to remember the sine, cosine, tangent progression on your own.

  • Saddle Our Horses, Canter Away Happily, To Other Adventures.

  • Silly old Henry, caught Albert Hugging two old Aunts.

  • Some Old Hulks
    Carry A Huge
    Tub Of Ale

  • Stupid Old Hitler
    Caused Awful Headaches
    To Our Airmen

  • Some Old Hag
    Cracked All Her
    Teeth On Asparagus

  • Some Old Hairy
    Camels Are Hairier
    Than Others Are

  • Smiles Of Happiness
    Come After Having
    Tankards Of Ale!!!

  • The Cat Sat
    On An Orange
    And Howled Hard

  • Some Opera Houses
    Can Always Have
    The Overture Again

  • Norman Sobieck from Michigan sent in the following:

    Oscar Had A Heap Of Apples, Some Came Today!

    Some = Oscar / Had
    Came = A / Heap
    Today! = Of / Apples

    for the cosecant, secant, and cotangent functions...

    Heather Ordered Harold An Albino Octopus, Cause She Can (or Could)

    Cause = Heather / Ordered
    She = Harold / An
    Can! = Albino / Octopus

  • David Greenberg sent in the following from his late geometry teacher, Jerry Vouso:

    Old Homes,
    Are Homes,
    Of Angels

    - again, you just have to remember the Sine, Cosine, Tangent progression on your own.

  • G. Bulmer who is British sent in the following mnemonic from his teacher:

    The Ordinary Army
    Simple Officers Have
    Curly Auburn Hair

    She pronounced it with quite a broad 'Geordie' accent (I come from the North East of England).

  • Joz from the UK sent in the mnemonic that he learned:

    Some of his chums are having trouble over algebra.

  • Paul Jackson sent in the following mnemonic:

    Of All The African Hairy Crocodiles Only Half Smell

    OAT AHC OHS (Tangent / Cosine / Sine)

  • Iain Little sent in the following mnemonic:

    Some old hags chant ancient hymns to old Albert

  • Jack Santcross sent in the following mnemonic that he learned in the late 1940s:

    Some old hags carry a huge tub of ale