plot (0,0), (-1,0), (0,4) and connect the dots
http://www.mathsisfun.com/sine-cosine-tangent.html
find the exact values of THE SIX TRIGONOMETRIC FUNCTIONS OF THE ANGLE THETA WHICH HAS A POINT ON THE TERMINAL SIDE OF (-1,4)
2 answers
(0 , 0), (-1 , 4).
X = -1 - 0 = -1.
Y = 4 - 0 = 4.
r^2 = X^2 + Y^2,
r^2 = (-1)^2 + 4^2 = 17,
r = sqrt(17).
sin(Theta) = Y/r = 4 / sqrt(17) =
4*sqrt(17) / 17.
cos(Theta) = X/r = -1/sqrt(17) =
-1*sqrt(17) / 17.
tan(Theta) = Y/X = 4 / -1 = -4.
csc(Theta) = 1/sin(Theta) = 17 / 4*sqrt(17) = 17*sqrt(17) / 4*17 =
sqrt(17) / 4.
sec(Theta) = r/X = 1/cos(Theta) =
17 / -1*sqrt(17) = -17*sqrt(17) / 17
= -1*sqrt(17).
cot(Theta) = 1/tan(Theta) = X/Y =
-1/4 = -(1/4).
X = -1 - 0 = -1.
Y = 4 - 0 = 4.
r^2 = X^2 + Y^2,
r^2 = (-1)^2 + 4^2 = 17,
r = sqrt(17).
sin(Theta) = Y/r = 4 / sqrt(17) =
4*sqrt(17) / 17.
cos(Theta) = X/r = -1/sqrt(17) =
-1*sqrt(17) / 17.
tan(Theta) = Y/X = 4 / -1 = -4.
csc(Theta) = 1/sin(Theta) = 17 / 4*sqrt(17) = 17*sqrt(17) / 4*17 =
sqrt(17) / 4.
sec(Theta) = r/X = 1/cos(Theta) =
17 / -1*sqrt(17) = -17*sqrt(17) / 17
= -1*sqrt(17).
cot(Theta) = 1/tan(Theta) = X/Y =
-1/4 = -(1/4).