if Tn=SINnA +COSnA, prove that 6T10 - 15T8 +10T6 - 1 = 0?

Answer 1

T^n = sin^nA + cos^nA
T^2 = sin^2A + cos^2A = 1
Therefore,
T^10 = 1
T^8 = 1
T^6 = 1
6T^10 - 15T^8 + 10T^6 - 1 =
6 - 15 + 10 - 1 = 0

Answer 2

use mathematical induction