Matematika

Pertanyaan

sin b = 5:13, tan a = 0,75 a dan b sudut lancip. nilai cos(a + b) =...?
sin b = 5:13, tan a = 0,75 a dan b sudut lancip. nilai cos(a + b) =...?

0 Comment.

2 Jawaban

  • tan a = 3/4 ; sin a = 3/5 ; cos a = 4/5
    sin b = 5/13 ; cos b = 12/13

    cos (a + b) = cos a cos b - sin a sin b
    cos (a + b) = 4/5 12/13 - 3/5 5/13
    cos (a + b) = 48/65 - 15/65
    cos (a + b) = 33/65

  • tan A = 0,75
    sin A = 3/5
    cos A = 4/5

    sin B = 5/13
    cos B = 12/13

    cos (A + B) = cos A cos B - sin A sin B
    cos (A + B) = 4/5.12/13 - 3/5.5/13
    cos (A + B) = 48/65 - 15/65
    cos (A + B) = 33/65

Pertanyaan Lainnya