Question

if cos20=k and cosx =2k^2-1 ,then the possible value of x between 0°and 360°are​

Answer 1

cos20 = 0.93

cosX = 2k^2-1

= 2(0.93× 0.93) -1

=1.7298-1

=0.7298

X = cos^-1(0.7298)

= (43.1)°