13.1 Right Triangle Trigonometry
ALGEBRA II
Evaluating 6 Trig. Functions
of theta
Sin
=
Cos
=
opp
hyp
csc
=
Tan
=
adj
Hyp
Sec
=
opp
adj
Cot
=
hyp
hyp
adj
opp
adj
opp
Abbreviations
•Sin- Sine
•Cos-Cosine
•Tan-Tangent
•Csc-Cosecant
•Sec-Secant
•Cot-Cotangent
Example 1:
Evaluate 6 Trig functions

3
4
Trig. Functions for future
calculations
1
csc  
sin 
1
sec  
cos 
1
cot  
tan 
Ex. 2 Let  be an acute angle of a
right triangle. Find the values of
the other five trigonometric

functions of  when
 Sec  =
12
5
Trig Values for Special
Angles

sin

cos

tan 
csc

sec

30
1
2
3
2
3
3
2
2 3
3
45
2
2
2
2
1
2
2
1
2
3
2 3
3
60
3
2
2
cot

3
1
3
3
Ex. 3
30 
15
x
Assignment
Solving a Triangle -Find 3
missing parts, angle & side

lengths
 Ex. 1) Given A = 35 degrees , c = 16
Ex. 2
 A support cable from a radio tower makes an
angle of 56 degrees with the ground. If the
cable is 250 ft. long, how far above the
ground does it meet the tower?
Ex. 5
 You are standing at the end of the shadow of
a giant sequoia, 150 ft from its base. The
angle of elevation to the sun is 63 degrees.
How tall is the tree?
Example 3:
FIND SIN A
formula
55
Plug in number
Cross multiply & solve for x
Answer