Page 9 - AP Unit 2 Vectors Student Binder_Neat
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AP 2.5   Dot Product and Angle Between Vectors

                  Name ____________________________________________ Date  ____________ Class___-

               Fill in the blank.

                1.  The ___________ of two vectors yields a scalar, rather than a vector.
                2.  If      is the angle between two nonzero vectors u and v, then cos       = _______________.
                3.  The vectors u and v are ____________ if      ∙      = 0.

               State the dot product of u and v.

                   4.        = 〈6, 3〉         = 〈2, −4〉      5.       = 〈−4, 1〉          = 〈2, −3〉

                        6.       = 5     +               = 3     −           7.      = 3     + 2              = −2     +     

                For 8-13, use the vectors      = 〈2, 2〉         = 〈−3, 4〉, and      = 〈1, −4〉 to find the indicated quantity. State
                whether the result is a vector or a scalar.

                8.      ∙         9.        ∙        10.       ∙ 2       11.  4     ∙        12. (3     ∙     )               13. (     ∙ 2    )    

                For exercises 14-19, use the dot product to find the magnitude of u.

                14.       = 〈−5, 12〉          15.      = 〈2, −4〉           16.      = 20     + 25    

                17.      = 6     − 10             18.       = −4                            19.      = 9    


                   20)

               a)   Find the dot product of the two vectors.   b)  Find the angle between the two vectors.


                   a = −2,5 ,b = 3,6                              a = 8i− 3 j,b = 2i − 7 j

              21) Show that the two vectors are orthogonal.


               a = 4,−1 ,b = 2,8



              22) Show that the vectors are parallel., and determine whether they have the same direction or opposite directions.


                   5
               a = i +10j,b = 3i+18 j                      a = 1,−4 ,b = −2,8
                   3
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