Projection formulas in a triangle for JEE

Formula

\(a=b\cos C+c\cos B,\quad b=c\cos A+a\cos C,\quad c=a\cos B+b\cos A\)

Variables: \(a,b,c\) are sides opposite angles \(A,B,C\).

Conditions: For any triangle.

Triangle transformations and relation derivations.