Math
posted by Tommy .
If I am give the the sides of a triangle, where
Side RA=4
Side AB=4.8
Side RB=7.1
How do I find Angle RAB?
Thanks!

Law of Cosines
C^2=a^2+b^22abCosC
so label your sides a, b, c
you want angle c to equal RAB
so RB=C
RA=a
AB=b