Question

Due Soon Need Help Geometry!

Answer 1

 

Some basic formulas involving triangles

\ a^2 = b^2 + c^2 - 2bc \textrm{ cos } \alphaa  2 =b  2+2 + c 2

−2bc cos α

\ b^2 = a^2 + c^2 - 2ac \textrm{ cos } \betab   2=

 

m_b^2 = \frac{1}{4}( 2a^2 + 2c^2 - b^2 )m   b2 = 41(2a 2 + 2c 2-b 2)

b

Bisector formulas

\ \frac{a}{b} = \frac{m}{n}  ba =nm  

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\ l^2 = ab - mnl  2=ab-mm

A = \frac{1}{2}a\cdot b = \frac{1}{2}c\cdot hA=  

\ A = \sqrt{p(p - a)(p - b)(p - c)}A=  

p(p−a)(p−b)(p−c)

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\iits whatever  A = prA=pr with r we denote the radius of the triangle inscribed circle

\ A = \frac{abc}{4R}A=  

4R

abc

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 - R is the radius of the prescribed circle

\ A = \sqrt{p(p - a)(p - b)(p - c)}A=  

p(p−a)(p−b)(p−c)

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