Question

Trigonometri kelas XI

Answer 1

Verified answer

Sin C = 2/akar 13. artinya y = 2 dan r = akar 13
dari dalil Phitagoras didapat x^2 = r^2 - y^2
r^2 = 13-4 = 9, maka x = 3
tan C = y/x = 2/3 ( karena lancip)
A + B + C = 180 (jumlah sudut sehingga)
A + B = 180 - C
tan (A+B) = tan (180-C)
= - tan C
= - 2/3
tan (A+B) = (tan A + tanB) / (1-tanA.tan)
-2/3 = (tan A + tan B) / (1- 13)
-2/3 = (tan A + tan B) / -12
tan A + tan B = -2/3 x -12
= 24/3
= 8
Jadi tan A + tan B = 8