Suppose 45Β° < πœƒ < 90Β°, let π‘Ž=log1/2(sinπœƒ), b = log1/2(cosπœƒ) ,𝑐 = log1/2(tanπœƒ), 𝑑 = log1/2(secπœƒ). Order π‘Ž, 𝑏, 𝑐, 𝑑 from the smallest to the largest.

since logx is an increasing function, logx < logy if x < y

so the logs are in the same order as the trig values:
cosΞΈ, sinΞΈ, tanΞΈ, secΞΈ
so, b,a,c,d

not sure what the 1/2 factor means; all it does is add log 1/2 to each value