Application of law of cosines to pentagons
A regular pentagon is inscribed in a circle of radius 4 centimeters. Make use of the law of cosines to find the perimeter of the pentagon. Show sketch and equation.
Proving the given equations by substitution.
Use the given substitution to show that equations are valid for 0 ≤ θ ≤ Π /2
1.If x = 2 Cos θ, Show that √(4 - x2) = 2sin θ
2.If x = 2 Sec θ, Show that √(x2 - 4) = 2 tan θ