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Thursday, June 19, 2014

Trigonometry Tricks


Sin = Perpendicular/Hypotenuse
Cos = Base/Hypotenuse
Tan = Perpendicular/Base

Make a sentence for it to memorize it easily, we make a sentence “some people have curly black hair through properly brushing”
Cesec, Sec and Cot are reverse of Sin, Cos and Tan...


A useful trick to remember is that all the trigonometric functions are periodic, that is, they repeat their values after a specific angle. For example, sine and cosine functions repeat after every 360 degrees, and tangent function repeats after 180 degrees. This goes for their inverses as well.


To learn the trigonometric table (yeah! I am talking about that sin, cos, tan and other side 30, 45, 60 and more degrees' table... ohhh...!!!), Watch this video (7:32 --- not so long)... It explains a very easy method to remember that... (Thank Goodness, Finally I found it..!!!)

(source: wikipedia)

 If you look at this, there are a number of different identities you can observe.

Reading across the central 1 in any direction gives reciprocal identities:

Reading down any triangle gives the standard identities (starting at the top left and going clockwise):

Reading a function and dividing the two consecutive clockwise or counter clockwise neighbors gives these identities:
(Starting at tan and going clockwise)

(Starting at tan and going counter-clockwise)

Reading a function and multiplying the two nearest neighbors gives these identities (starting at tan and going clockwise):