help fast please?

Attachment image

1 Answer

Relevance
  • 1 month ago
    Favorite Answer

    I won't solve them for you, you need to learn how... so here is a hint  for each part.

    Hint:   

    1.   calculate  cos (a)  and   sin (ß)    by using  pythagorean  Thm, 

    ( sin@)^2  + (cos@)^2 = 1       so you can find  cos a, then  sin ß

    For example   cos a =  √ [ 1 - ( sin a )^2 ] , I get   20/ 29

    2.  Decide  the  sign,  +  or  -  on each      angle  a is in Quadrant I  so  cos a  is  also  +

    3.   Now that you have  sine, cosine for each  angle  use the trig identities...

    sin ( a + ß ) = sin a cos ß  + cos a sin ß 

    cos( a - ß) = cos a cos ß + sin a cos ß

    tan ( a - ß) = [ tan a - tan ß ] / [ 1 + tan a tan ß ]

    It's a lot of multiplication and simplifying, but you need the practice to be able to do it on a test.

Still have questions? Get your answers by asking now.