How do you find the exact value of the six trigonometric functions of the angle whose terminal side passes through (-0.5, 4.5)?

1 Answer
Feb 27, 2018

As below.

Explanation:

x = -0.5, y = 4.5

r = sqrt(x^2 + y^2) = sqrt((-1/2)^2 + (9/2)^2 )= sqrt(82/4)= sqrt(41/2)

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sin alpha = y / r = (9/2) / sqrt(41/2) = 9 / sqrt82

cos alpha = x / r = -(1/2) / sqrt(41/2) = -(1/sqrt82)

tan alpha = y / x = -(9/2) / (1/2) = -9

csc alpha = 1 / sin alpha = sqrt82 / 9

sec alpha = 1/cos alpha = - sqrt82

cot alpha = -(1/9)