tolong dijawab yah !

TriGonoMetRi

tan (A + B)/2 / tan (A - B)/2
= [sin (A + B)/2 . cos (A - B)/2] / [cos (A + B)/2 . sin (A - B)/2]
= 1/2 (sin A + sin B) / 1/2 (sin A - sin B)
= (sin A + sin B) / (sin A - sin B)

•
x/sin A = y/sin B
sin A = x/y sin B

lanjutin
= (sin A + sin B) / (sin A - sin B)
= (x/y sin B + sin B) / (x/y sin B - sin B)
= (x/y + 1) / (x/y - 1)
= (x + y)/(x - y)

Jwaban di  Lampiran
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