a: \(sin15=\dfrac{\sqrt{6}-\sqrt{2}}{4};cos15=\dfrac{\sqrt{6}+\sqrt{2}}{4};tan15=2-\sqrt{3};cot15=2+\sqrt{3}\)
\(sin52=0.79;cos52=0.61;tan52=1.28;cot52=0.78\)
\(sin64=0.9;cos64=0.44;tan64=2.05;cot64=0.49\)
b: \(sin15^020'=0.26;cos15^020'=0.96;tan15^020'=0.27;cot15^020'=3.65\)
\(sin52^018'=0.79;cos52^018'=0.61;tan52^018'=1.29;cot52^018'=0.77\)