The arctangent is the inverse tangent function. Since. tan Ï/4 = tan 45Âº = 1. The arctangent of 1 is equal to the inverse tangent function of 1, which is equal to Ï/4 radians or 45 degrees: arctan 1 = tan-1 1 = Ï/4 rad = 45Âº. 1  Arctan.  Arctan calculator.
Arteries, on the other hand, are classified as systemic (part of the cardiovascular system), pulmonary (carry blood to the lungs), aorta and arterioles. Arteries carry bright red blood as it is oxygenated while veins have the dark red blood. Arteries progressively divide into smaller tubes unlike veins.
Making the world better, one answer at a time. Arteries are the blood vessels that take blood away from the heart. Blood in the arteries are brown as they go away from the heart and blood travelling to the heart in veins are coloured red as it has just been replenished when passing the lungs.aking the world better, one answer at a time. Arteries are the blood vessels that take blood away from the heart. Blood in the arteries are brown as they go away from the heart and blood travelling to the heart in veins are coloured red as it has just been replenished when passing the lungs.