เทคนิคจำค่า sin cos tan ในฟังก์ชันตรีโกณมิติ

cos sin  The row of cos is as same as the row of sin just in the reverse order Each value in the row of tan is obtained by dividing the corresponding values of sin by cot θ = cos θsin θ Trigonometric Identities of Opposite Angles In trigonometry angle measured in the clockwise direction is measured in

cos, in terms of sin and, Defining relations for tangent, cotangent, secant, and cosecant in terms of sine and cosine sin squared + cos squared = 1, The 14 COS X = - sin x dx dx d 15 tan x = sec²x d X 16 cot x = -cosec²x dx dx d d 17 sec x = sec x tan x 18 cosecx = cos ecx cotx

Formule per gli archi associati per seno e coseno · sin(−α) = cos; cos(−α) = sin · sin(+α) = cos; cos(+α) = ตัวอย่ำงที่2 จำกรูปสำมเหลี่ยมมุมฉำก XYZ ที่กำหนดให้จงหำค่ำของ sin X วิธีท า โดยใช้ทฤษฎีบทพีทาโกรัสจะได้ 2 = 2 − 2