Reduce the fraction -20t^5u^2v^3/48t^7u^4y

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[15 points]find the quotient with the restrictions. (x^2 - 2x - 3) (x^2 + 4x + 3) ÷ (x^2 + 2x - 8) (x^2 + 6x + 8)

Prove sin2a + cos2a - 1 / sin2a + cos2a + 1 = 1 - tana / 1 + cota