Trig – In a Nutshell
Download
Report
Transcript Trig – In a Nutshell
Trig – In a Nutshell
Help I’m trapped in a nutshell
The Unit Circle
(0,1)
+,+
-,+
(1,0)
(-1,0)
+,-
-,(0,-1)
2
+
θ
-
3
2
2
These are the reference triangles
1
30
1
1
2
6
45
2
2
4
2
2
3
2
3
2
1
60
3
1
2
Trigonometric Functions
r
y
θ
x
opp y
sin
hyp r
1
hyp r
csc
sin opp y
adj x
cos
hyp r
sec
sin opp y
tan
cos adj x
1
cos adj x
cot
tan sin opp y
1
hyp r
cos adj x
Conversion
Radians to Degrees:
Radians
180
5
12
Degrees to Radians:
130
Degrees
180
Lets quickly review
30
6
45
4
60
3
90
2
5
6
3
4
5
3
3
2
150
135
300
270
Examples
5
1. Find sin
6
1
2
150
What Quadrant? Q II
Pull out Triangle
150
1/2
60
1
30
Draw down
side to x-axis
3
2
What Happens if…
If you land on an axis, there is no triangle. So
instead of using sides of the triangle, use x, y and
r. Unless otherwise specified, r = 1.
1. Find sin π, cos π and tan π.
y 0
sin 0 What would csc be?
r 1
x 1
cos 1
r 1
y 0
tan 0
x 1
(-1,0)
Examples
3
1. If sin x and x is in QII find all six Trig Functions
5
Examples
Find the values of the six trig. functions of , if is an angle
in standard position with the point (4 , 3) on its terminal ray.