tlong di jawab pakai cara ya kak no 5 & 6 aj

jawb
5. 
A lancip
B tumpul

cos A = 3/5 = x/r 
trilpel  x,y,r = 3,4 5
tan A = y/x= 4/3

sin B = 12/13= y/r
triple = x,y,r = 5,12,13
tan B = - y/x= - 12/5

tan (A+B) = (tan A + tan B) / (1 - tan A . tan B)
= (4/3 - 12/5) / ( 1 -  4/3 (-12/5))
= (4/3  -12/5) / (1 + 48/15) .....kalikan 15/15
= (20 - 36) / (15+48)
= - 16/63

6.
B lancip
A tumpul
sin B = 12/13 = y/r
triple = x,y,r = 5,12,13
tan B = y/x = 12/5

sin A = 3/5 = y/r
triple  x,y,r = 4,3,5
tan A = y/x = - 3/4

tan (A - B ) =  (tan A - tan B) / ( 1 + tan A tan B)
tan (A - B) = (-3/4 -  12/5) / ( 1 + (-3/4. 12/5))
tan (A - B) = (- 3/4 - 12/5) / (1 - 36/20) ....kalikan 20/20
tan (A - B) = (-15 - 48)/ (20 - 36) = -63/-16
tan (A - B)= 63/16