1.Cos2A+cos4A-cos3A=0, for 0≤A≤360

2.Show that Cos^-1(A)=Sin^-1 square root (1-A^2), (Inverse Trigonometric Function)

3.2cos3A-sin3A=Square root 5, for 0≤A≤360

4.Cos(A-∏/6) + sin (∏/6-A)=1, for 0≤A≤360

5.Tan3A=cot(∏/3-A), for 0≤A≤360

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