Question

please solve it.. eak question bhi solve kardoge to kafi hai please solve it.. ​

Answer 1

Answer:

L.H.S.

= 8cos³20 – 8sin³10 – 6cos20 + 6sin10

= 2(4cos³20 – 4sinn³10 – 3cos20 + 3sin10)

= 2(4cos³20 - 3cos20 + 3sin10 – 4sin³10)

= 2(cos³20 + sin³10)   [∵ cos³A = 4cos³A – 3cosA and sin³A = 3sinA – 4sin³A]

= 2(cos60 + sin30)

= 2(1/2 + 1/2)

= 2

1st ans sry I dont know abt 2nd