U3 A1 Flashcards
What is the order of pairs in the unit circle (in terms of cos and sin)
(Cos, sin)
What does the radius of the u it circle represent
Hypotenuse of special triangle
What is 0 or 360 degrees on the unit circle
(1,0)
What is 90 degrees on the unit circle
(0,1)
What is 180 degrees on the unit circle
(-1,0)
What is 270 degrees on the unit circle
(0,-1)
Where does the terminal arm always start, and which way does it rotate
Positive x axis
Rotates counterclockwise
What is the angle in standard position
Angle formed between the positive x axis and the terminal arm
What is the “angle in standard position” also called
Rotation angle
What is the reference angle (and how is it written)
Angle between the terminal arm and the closest x axis
Theta sub r
What is always the domain of a reference angle
Greater than on equal to 0 degrees, less than or equal to 90 degrees
How are the quadrants labelled on a graph
Q1 is top right (and label counterclockwise)
Q4 is bottom right
Positive angle: when the terminal arm is rotated in a ______ direction
Counter clockwise
Negative angle: when the terminal arm is rotated in a ______ direction
Clockwise
Coterminal angle: angle that are generated so that the ______arm is in the exact _____ position
Terminal
Same
What is the principle angle
Small positive coterminal angle
What is the formula for conterminal angles (and what do the variables represent)
P + 360 degrees (n), n € I
P=principle angle
n= # of rotations
How do you determine coterminal angles
Add/subtract multiples of 360 from original angle
What is the formula that relates radian to arc length
And what is theta measured in
Theta = a/r
Theta is measured in rads
What is 360 degrees in rads
2(Pi)
What is 180 degrees in rads
Pi
Conversion factor for degrees to rads
1 degree = (Pi/180) rads
Conversion factor for rads to degrees
1 rad = (180/Pi) degrees
What is 30 degrees in rads
Pi/6
What is 45 degrees in rads
Pi/4
What is 60 degrees in rads
Pi/3
What is 90 degrees in rads
Pi/2
WHAT DO YOU HAVE TO MAKE SURE OF WHEN YOUR’RE USING CALC
That it’s in the correct mode
Never put a ____ ratio when taking the inverse to find the angle
(And What do you do instead)
Negative
Use the positive ratio
What’s the ratio for sin theta
y/r
What’s the ratio for cos theta
x/r
What’s the ratio for tan theta
y/x
What is the ratio for csc theta
And what is it the reciprocal of
r/y
Reciprocal of sin theta
What is the ratio for sec theta
And what is it the reciprocal of
r/x
Reciprocal of cos theta
What is the ratio for cot theta
And what is it the reciprocal of
x/y
Reciprocal of tan theta
How do CAST laws apply to reciprocal ratios
follow the same cast rule as their reciprocal ratio
What is (root 3)(root 3)
3
How to solve this:
csc (-5Pi/3)
(And what’s the answer)
1) recognize Pi/3 = 60 degrees
2) -5(60) = -300 degrees
3) draw -300 degrees on graph
4) find reference angle (60 degrees)
5) use hand rules to determine the sin ratio the flip it (since it’s csc)
6) rationalize the denominator and the answer is 2(root3)/3
What is cos theta in terms of the unit circle
X
What is sin theta in terms of the unit circle
Y
What is tan theta in terms of cos and sin
sin/cos
How to label the CAST law
C is in the bottom right quadrant
And start labelling counterclockwise
Steps for finding a trig ratio
1) determine quadrant
2) determine reference
3) determine ratio (finger rules)
4) determine if negative or positive based off CAST law