Jawabanmu

2014-06-24T21:40:44+07:00
COS(A-B)= COSACOSB+SINASINB
              =3/5.(-24/25)+4/5.7/25
              =-72/125+28/125
              =-44/125
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Jawaban paling cerdas!
2014-06-24T21:40:47+07:00
SinA = 4/5 maka CosA = 3/5 dan SinB = 7/25 maka CosB = 24/25
Cos(A-B) = CosACosB + SinASinB
               = 3/5(24/25) + 4/5(7/25)
               = 72/75 + 28/75
               = 100/75
               = 4/3
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