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
 Some Of Her Children Are Having Trouble Over Algebra.
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Sat On Her
Chair And Hollered.
 (from Ann Azevedo)  Stamp Out Homework Carefully, As Having Teachers Omit Assignments.
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Skipped Over Heaven
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 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.

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Carry A Huge
Tub Of Ale 
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Caused Awful Headaches
To Our Airmen 
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Cracked All Her
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Camels Are Hairier
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Come After Having
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