Law of Tangents
Triangles and law of tangents.
The "Law of Tangents" can be used to calculate the angles or sides of a triangle.
Law of Tangents
The "Law of Tangents" can be expressed as
(a + b) / (a  b) = tan 1/2 (A + B) / tan 1/2 (A  B) (1)
where
a, b and c = length of sides in triangle (m, ft ...)
A, B and C = angles in the triangle (degrees)
Pythagorean theorem
The Pythagorean theorem can be expressed as
a^{2} + b^{2} = c^{2} (2)
Law of sines
The Law of sines can be expressed as
a / sin(A) = b / sin(B) = c / sin(C) (3)
Angles
If the length of all three sides in the triangle are known  the angles can be calculated as
A = arccos((b^{2} + c^{2}  a^{2}) / (2 b c)) (4a)
B = arccos((a^{2} + c^{2}  b^{2}) / (2 a c)) (4b)
C = arccos((a^{2} + b^{2}  c^{2}) / (2 a b)) (4c)
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Mathematics
Mathematical rules and laws  numbers, areas, volumes, exponents, trigonometric functions and more.
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