P is a point on the terminal side of θ in standard position. Find the exact value of the six trigonometric functions for θ. P(-8, -8)

Ans:

cotangent: 1
secant: negative square root 2
cosecant: negative square root 2
sin: square root 2 / 2
cosine: square root 2 / 2
tan: 1

User Icon for MathMate MathMate answered
9 years ago

cotangent: 1

secant: negative square root 2
cosecant: negative square root 2
*sin: square root 2 / 2
*cosine: square root 2 / 2
tan: 1

The terminal side lands in the third quadrant, where only tangent (and cotangent) is positive. So sine (cosec) and cosine (sec) are all negative.

Use this as a guide:

S|A
---
T|C

Starting from Q1, we can use
"All Students Take Calculus" to help memorize the positive functions.
(A=all 6 functions)

User Icon for Anonymous Anonymous answered
9 years ago

So I change sin and and cosine to make them negative?

User Icon for MathMate MathMate answered
9 years ago

Yes, that is correct, but try to understand why you do that by studying the unit circle.

User Icon for Anonymous Anonymous answered
9 years ago

Thanks! Yes, I will study it.

User Icon for Explain Bot Explain Bot answered
11 months ago

To find the exact values of the six trigonometric functions for angle θ, we can use the information given about point P(-8, -8) on the terminal side of θ in standard position.

First, let's find the coordinates of point P:
The x-coordinate of point P is -8, and the y-coordinate is -8.

Next, we can use the coordinates of point P to calculate the values of the trigonometric functions.

1. sine (sin):
sin = y/r
sin = (-8) / sqrt((-8)^2 + (-8)^2)
sin = -8 / sqrt(64 + 64)
sin = -8 / sqrt(128)
sin = -8 / (8 * sqrt(2))
sin = -1 / sqrt(2)
To simplify further, we multiply both the numerator and denominator by sqrt(2):
sin = (-1 / sqrt(2)) * (sqrt(2) / sqrt(2))
sin = -sqrt(2) / 2

2. cosine (cos):
cos = x/r
cos = (-8) / sqrt((-8)^2 + (-8)^2)
cos = -8 / sqrt(64 + 64)
cos = -8 / sqrt(128)
cos = -8 / (8 * sqrt(2))
cos = -1 / sqrt(2)
Similar to sin, we can simplify further:
cos = (-1 / sqrt(2)) * (sqrt(2) / sqrt(2))
cos = -sqrt(2) / 2

3. tangent (tan):
tan = y/x
tan = (-8) / (-8)
tan = 1

4. cotangent (cot):
cot = 1 / tan
cot = 1 / 1
cot = 1

5. secant (sec):
sec = 1 / cos
sec = 1 / (-1 / sqrt(2))
sec = -sqrt(2)

6. cosecant (csc):
csc = 1 / sin
csc = 1 / (-1 / sqrt(2))
csc = -sqrt(2)

Therefore, the exact values of the six trigonometric functions for θ are:
sin = -sqrt(2) / 2
cos = -sqrt(2) / 2
tan = 1
cot = 1
sec = -sqrt(2)
csc = -sqrt(2)