If sin a / sin B = C, then a / b =? RT
Since Sina / SINB = A / B, a / b = C
Given a = (COS α, sin α), B = (COS β, sin β), and a ‖ B, then β - α=
∵a‖b
∴cosa*sinb-sina*cosb=0
cosasinb=sinacosb
sinb=tanacosb
tanb=tana
∴b-a=kπ/2(k∈Z)
If sin (B-A) = 0, then B = a
Not necessarily, B-A = 180 or 90 is OK
What is the relationship between sin a and sin B?
In the same triangle, according to the sine theorem
a/sinA=b/sinB
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