Respuesta :

tk6199235

Answer:

b. cos²3x - sin²3x = cos6x

if its wrong sorry

hope this helps you☺️☺️

gayanepoghosyan

Answer:

B and D

Step-by-step explanation:

B.cos²3x-sin²3x=cos6x   ( as cos²a -sin² a = cos 2a)

D.(sinx+cosx)²=sin²x+cos²x+2sinxcosx=1+sin2x

Otras preguntas