Question

1+cos b/sin b=sin b/1-cos b

Answer 1

(1 + cosb)/sinB = sinb/(1 - cosB)
√((1 + cosb)²/sin²b) = sinb/(1 - cosB)
√((1 + cosb)(1 + cosB)/(1 - cos²b)) = = sinb/(1 - cosB)
√((1 + cosb)/(1 - cosb)) = sinb/(1 - cosB)
√((1 - cos²b) / (1 - cosb)²) = sinb/(1 - cosB)
√(sin²b/(1 - cosb)²) = sinb/(1 - cosB)
sinb/(1 - cosb) ≡ sinb/(1 - cosB)
Тождество доказано