tolong dijawab ya buat latihan UKK!

16.
sin A= 3/5
cos A = 4/5
tan A = 3/4

sinB= 12/13
cos B = 5/12
tan B = 12/5

sin A. tanB  - tan A sin B =
= (3/5)(12/5) - (3/4)(12/13)
= (36/25) - (36/52)
= 243/325

17. Buktikan
(1-sin² A)(1+ tan² A)  = 1
= (cos² A)(1 + sin² A/cos² A)
= cos²A + sin² A
 = 1

18. lim(x->0)  (2x)/ √{(4+3x) - √(4-3x)}=
= 2x {√(4+3x) + √(4-3x)} / {(4+3x-4 +3x)}
= 2x {√(4 +3x) + √(4-3x)}/ (6x)
= 1/3 {√(4+2x) + √(4-3x)}
x = 0
= 1/3 (√4 +√4)
= 1/3 (4)
= 4/3
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