Laws

From which law follows directly the validity of Pythagoras' theorem in the right triangle?


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Solution:

c**2 = a**2 + b**2 - 2ab cos gamma ; ; ; ; gamma = 90° Rightarrow cos 90° =0 ; ; c**2 = a**2 + b**2 - 2ab cos 90° ; ; c**2 = a**2 + b**2 ; ;

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To solve this example are needed these knowledge from mathematics:

Cosine rule uses trigonometric SAS triangle calculator. See also our trigonometric triangle calculator. Pythagorean theorem is the base for the right triangle calculator.

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