Trigonometry Flashcards
sin^2x + cos^2x =
1
tanx =
sinx/cosx
cosecx =
1/sinx
secx =
1/cosx
cotx =
1/tanx or cosx/sinx
(sin^2x + cos^2x)/sin^2x =
1 + cot^2x = cosec^2x
(sin^2x + cos^2x)/cos^2x =
tan^2x + 1 = sec^2x
sin(A+B) =
sinAcosB + cosAsinB
sin(A-B) =
sinAcosB - cosAsinB
cos(A+B) =
cosAcosB - sinAsinB
cos(A-B) =
cosAcosB + sinAsinB
tan(A+B) =
(tanA + tanB)/(1 - tanAtanB)
tan(A-B) =
(tanA - tanB)/(1 + tanAtanB)
sin2A =
2sinAcosA
cos2A =
1) cos^2A-sin^2A
2) 2cos^2A - 1
3) 1 - 2sin^2A
tan2A =
2tanA/(1 - tan^2A)
2sinAcosB =
sin(A+B) + sin(A-B)
2cosAsinB =
sin(A+B) - sin(A-B)
2cosAcosB =
cos(A+B) + cos(A-B)
2sinAsinB =
cos(A+B) - cos(A-B)
sinP + sinQ =
2sin((P+Q)/2)cos((P-Q)/2)
sinP - sinQ =
2cos((P+Q)/2)sin((P-Q)/2)
cosP + cosQ =
2cos((P+Q)/2)cos((P-Q)/2)
cosP - cosQ =
-2sin((P+Q)/2)sin((P-Q)/2)
sin^2A=
1/2(1-cos2A)
cos^2A=
1/2(1+cos2A)
sin^2A/2=
1/2(1-cosA)
cos^2A/2=
1/2(1+cosA)
sin3A=
3sinA-4sin^3A
cos3A=
4cos^3A-3cosA
tan3A=
(3tanA-tan^3A)/(1-3tan^2A)
State in degrees the exact values of sin30, sin45, sin60, sin90, and sin180.
1/2, 1/root2, root3/2, 1, 0
State in degrees the exact values of cos30, cos45, cos60, cos90, cos180
root3/2, 1/root2, 1/2, 0, -1
State in degrees the exact values of tan30, tan45, tan60, tan90, tan180
1/root3, 1, root3, -, 0
