Kategorier: Alle - identities - angles - trigonometry - formulas

af Sean Leow 13 år siden

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R-formula and Trigonometry(Sean Group)

The text covers various fundamental concepts and formulas in trigonometry, presenting a comprehensive overview of trigonometric ratios, identities, and the R-formula. It starts by detailing specific angle values for sine, cosine, and tangent functions, and then introduces key addition and subtraction formulas for trigonometric functions.

 R-formula and Trigonometry(Sean Group)

R-formula and Trigonometry(Sean Group)

R-formula

Tan alpha = b/a
Where R=Square root of Asquare + b Square
acosx+bsinx=Rcos(x-a)/ acosx-bsinx=Rcos(x+a)
asinx+bcosx=R sin(x+a)/ asinx-bcosx= Rsin(x-a)

Double angle formulae

tan2A=2tanA/1-tansquare A
cos2A=cos square A- sin square A/ 2cos square A- 1/ 1-2sin square A
sin2A=2sinAcosA

Addition formulae

cos(a-b)=cosacosb+sinasinb
tan(a-b)=tana-tanb/1+tanatanb
tan(a+b)=tana+tanb/1-tanatanb
cos(a+b)=cosacosb-sinasinb
sin(a-b)=sinacosb-cosasinb
sin(a+b)=sinacosb+cosasinb

trigo ratio

tan60=square root 3
tan45=1
tan30=1/squareroot 3
cos60=1/2
cos45=1/squareroot2
cos30=squareroot 3 /2
sin60=squareroot 3 /2
sin45=1/square root 2
sin30=1/2

Trigo identites

sin square x+ cos sqaure x=1
1+tan square= sec square
cosecx=1/sinX
1+cot square = cosec square
secx=1/cosx
Cotx=1/tanx
Tanx= Opposite/adjacent

4th quadrant cosine positive

3rd quadrant tangent positive

2nd quadrant sine positive

1st quadrant all positive

1degree=π/180degree

1 radian=180degree/π

Cosx=Adjacent/hypotenus

Sinx=Opposite/Hypotenus