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KUADRAN III (sin -,cos -,tan +)
x^2 = r^2 - y^2
x^2 = 5^2 - 3^2
x^2 = 25 - 9
x^2 = 16
x = akar 16
x = 4
sin a = -3/5
cos a = -4/5
tan a = 3/4

KUADRAN II (sin +,cos -,tan -)
y^2 = r^2 - x^2
y^2 = 25^2 - 24^2
y^2 = 625 - 576
y^2 = 49
y = akar 49
y = 7
cos b = -24/25
sin b = 7/25
tan b = -7/24

cos a sin b + tan a tan b
= -4/5(7/25) + 3/4(-7/24)
= -28/125 - 21/96
= -28/125 - 7/32
= -896/4000 - 875/4000
= -1771/4000 (c)