nomor 8 dong tolongg sekalian caranya abaikan coretannya

tan = depan/ samping
maka sisi depan a=2
samping = 3
miring =√3²+2²=√13
maka
sin(90-a)= cos a
cos (180-a)= -cos a
tan(270+a)= - cot a
cot (360-a)= - cot a
jadi = cos a-(-cos a) / -2cot a
2cos / -2cot a
karena di kw 2 tan,cos,sex,dan cot bernilai negatif
= 2(-3/√13)/ -2(-3/2)
= 6/√13/ 3
= -2/13√13 <A>
Maaf kalau salah

Tan a = -2/3 = depan/samping
Miring = √(2^2 + 3^2) = √(4 + 9) = √13
Karena a dikuadran 2 maka sin a bernilai positif
sin a = depan/miring = 2/√13 . √13/√13 = (2/13) √13

[sin (90° - a) - cos (180° - a)] / [Tan (270° + a) + cot (360 - a)]
= (cos a - (-cos a)) / (- cot a - cot a)
= (2 cos a) / (-2 cot a)
= cos a / (- cot a)
= cos a . -tan a
= cos a . -(sin a)/(cos a)
= - sin a
= - (2/13) √13