In this lesson, we will have mnemonics and songs to help you remember
• Remember SOH-CAH-TOA
SOHCAHTOA, and how use you can use SOHCAHTOA to help you remember the right triangle definitions of the trig functions, assuming that you can remember to spell SOHCAHTOA.
Sin = Opposite/Hypotenuse
Cos = Adjacent/Hypotenuse
Tangent = Opposite/Adjacent
A SOH-CAH-TOA mnemonic: Some Old Horses Can Always Hear Their Owner’s Approach
• Oscar/Had (sin) A/Heap (cos) Of/Apples (tan)The Old Arab Carried A Heavy Sack Of Hay
• ASTC (Where are they positive?)
Which trig functions are positive in each quadrant:
All in Quadrant I,
Sine in Quadrant II,
Tangent in Quadrant III,
Cosine in Quadrant IV.
Mnemonics include “A Smart Trig Class”, “All Students Take Calculus”, “All Stores Take Cash”, and “Aunt Sally Tickles Cobras” (Cats, Camels, Cougars, Chimps, Caribou ...)This video demonstrates the ASTC rule used to determine the sign of the trigonometric function in each quadrant.
We can use a mnemonic like CAST or ASTC - All Students Take Calculus to remember the signs in the 4 quadrants.
Rotate to landscape screen format on a mobile phone or small tablet to use the Mathway widget which allows your to practice solving Algebra, Trigonometry, Calculus and other math topics.
We welcome your feedback, comments and questions about this site or page. Please submit your feedback or enquiries via our Feedback page.