Pls, can anyone help me, getting problem solutions? When following details are given?: Let ABC be a triangle with side lengths a=b=1, c=x (unknown) and angles α=A=2π/5, β=B=2π/5, γ=C= π/5
1) Show that cos(2π/5)=x/2
2) Let D be a point on the edge of BC such that AD bisects the angle BAC. Show that AD and CD both have same length x
3) Using cosine rule in the triangle ABD, show that x2+x-1=0
4) Deduce that cos(2π/5) = (√5-1)/4
1) Show that cos(2π/5)=x/2
2) Let D be a point on the edge of BC such that AD bisects the angle BAC. Show that AD and CD both have same length x
3) Using cosine rule in the triangle ABD, show that x2+x-1=0
4) Deduce that cos(2π/5) = (√5-1)/4
1 Answer
See explanation.
Explanation:
Convert radians to degrees:-
1.) cos
:. L.H.S.=R.H.S.
2.)
in