Trigonometric Ratios

  Sine = Opposite              Tangent = Opposite 
            Hypotenuse                        
    Adjacent    
            = O                                      = O               
            H                                          A
        Cosine = Adjacent                  =A             
                   Hypotenuse                  H

 

 

 

   ß*this side never changes*à                    
Hypotenuse – the longest side, opposite the right angle.
Opposite – the other side, opposite the angle you’re looking at.
Adjacent – the side next to or right beside the angle you’re looking at
* Your O and your A changes depending on what angle you’re looking at*

  Find –A                Find –C  
Sin A = 4               Sin C =3                  
             5                            5
Cos A =3              Cos C =4
             5                            5
Tan A =4             Tan C =3
             3                          4


Calculating Angles Using Trig          Ratios

To get this answer use your calculator and one of the following do as the 
 Push à 2nd F or shift  |   Pushà decimal
Pushà Sin/Cos/Tan      |   Pushà 2nd
Pushà decimal             |   Pushà Sin/Cos/Tan
Pushà =                      |   Pushà =

Ex.  Sin=3           Cos= 4       Tan=3 
               5                    5                4
            =0.6              =0.8           =0.75
       Sin=36.86   Cos=36.86 Tan=36=86

Calculating Decimals Using Trig Ratios

To get this answer use your calculator and one of the following do as the 
Pressà Cos/Sin/ Tan            |   Pressà Whole # (degree)
Pressà whole # (degree)      |   Pressà Cos/Sin/Tan
Pressà =                              |   Pressà =

Ex.  Cos 75 = 0.2588
        Sin 12 = 0.2079

Calculating Side Length Using Trig Ratios

To find the side length you must make the degree into a decimal.

Then depending on the side length you are finding you divide or you multiply 

Ex. 
      SOH
    Sin43= a    
               67
    0.6819=a
                67
67 X 0.819=a
         45.68=a
 there for side BC or a equals 45.68