WAEC - Further Mathematics (2020 - No. 3)

If cos x = -0.7133, find the values of x between 0\(^o\) and 360\(^o\)

44.5\(^o\) , 224.5\(^o\)

123.5\(^o\) , 190.5\(^o\)

135.5\(^o\) , 213.5\(^o\)

135.5\(^o\) , 224.5\(^o\)

cos x = -0.7133

x = cos \(^{-1}\)(0.7133)

= 44.496\(^o\)

x = 180 - 44.495\(^o\)

x = 135.5\(^o\)

and x = 180\(^o\) + 44.495\(^o\)

= 224.5\(^o\)