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October 21

Angles to all three axes, symmetrical equation?

Resolved

Let p be a point in the first octant. Let a be the angle between OP and the X axis, b be the angle between OP and the Y axis and c be the angle between OP and the Z axis. Is there a symmetrical equation that allows any one of the three to be calculated from the other two? My guess is that it is Cos^2(a)+Cos^2(b)+Cos^2(c)=1, but I'm not sure of any examples that would show that other than those on the XY, YZ or XZ planes.Naraht (talk) 17:59, 21 October 2015 (UTC)[reply]

See Direction cosine. --RDBury (talk) 18:10, 21 October 2015 (UTC)[reply]

Thanx, perfect.Naraht (talk) 19:32, 21 October 2015 (UTC)[reply]