Question

if A=30 degree, verify that cos2A=cos^2A-sin^2A = 2cos^2A-1

Answer 1

cos 2A = 1/2
cos ^2A - sin^2A = 3/4 - 1/4 = 1/2
2 cos ^2A -1 = 2*3/4 - 1 = 3/2 -1 = 1/2

Answer 2

Answer:

happy to help you........

❣️❣️❣️❣️❣️❣️❣️❣️❣️❣️