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.
The chief difference between arteries and veins is the job that they do. Arteries carry oxygenated blood away from the heart to the body, and veins carry oxygen-poor blood back from the body to the heart. Your body also contains other, smaller blood vessels.Here is how blood travels in vessels through the body:he chief difference between arteries and veins is the job that they do. Arteries carry oxygenated blood away from the heart to the body, and veins carry oxygen-poor blood back from the body to the heart. Your body also contains other, smaller blood vessels. Here is how blood travels in vessels through the body: