Difference between revisions of "Trigonometry"

Revision as of 22:58, November 17, 2012 (view source) Brenden (Talk | contribs) ← Older edit		Revision as of 17:21, June 28, 2015 (view source) JoeyJ (Talk | contribs) (Add formulas) Newer edit →
Line 7:		Line 7:
	*CAH: Cosine = adjacent over hypotenuse		*CAH: Cosine = adjacent over hypotenuse
	*TOA: Tangent = opposite over adjacent		*TOA: Tangent = opposite over adjacent
		+
		+	==Formulas==
		+	Complementary formulas:
		+	:<math>\sin(90^\circ-\alpha) \, = \, \cos\alpha</math>
		+	:<math>\cos(90^\circ-\alpha) \, = \, \sin\alpha</math>
		+
		+	Pythagorean trigonometric identity:
		+	:<math>\sin^2\alpha + \cos^2\alpha \, = 1</math>
	==External links==		==External links==

---

Revision as of 17:21, June 28, 2015

Trigonometry is the study of angles and triangles, relying heavily on three basic functions: sine, cosine and tangent, and their inverses, Cotangent (Cot), Secant (sec) and Cosecant (csc). These functions are abbreviated as "sin", "cos" and "tan".

These functions are defined by reference to a "right triangle," which is a triangle in which one angle is 90 degrees.

A way to remember the relationships is the mnemonic SOH-CAH-TOA ("soak a toe"). Think of a man soaking his toe in a tub of water - preferably a three-sided tub!

• SOH: Sine = opposite over hypotenuse
• CAH: Cosine = adjacent over hypotenuse
• TOA: Tangent = opposite over adjacent

Formulas

Complementary formulas:

Pythagorean trigonometric identity:

External links

• Trigonometry and Right Triangles