" (vi) "cos18^(@)=sin72^(@)=(sqrt(10+2sqrt(5)))/(4)

Prove that: cos18^(0)=(sqrt(10+2sqrt(5)))/(4)

Prove that: sin36^(0)=(sqrt(10-2sqrt(5)))/(4)

Prove that: cos18^0=(sqrt(10+2sqrt(5)))/4 .

3 cos72^(@)-4" sin"18^(@)=

Statement -1: If xin[-1//sqrt(3),1//sqrt(3)] then cot^(-1)((3x-x^(3))/(1-3x^(2)))=cos^(-1)((1-x^(2))/(1+x^(2)))rarrx=sqrt(25-10sqrt(5))/(5) statement -2: sin18^(@)=sqrt(5-1)/(4) and cos18^(@)=sqrt(10+2sqrt(5))/4

Prove that (i) "sin"^(2) 24^(@) - sin^(2) 6^(@) =((sqrt(5)-1))/(8) " "(ii) "sin"^(2) 72^(@) - cos^(2) 30^(@) =(sqrt(5)-1)/(8)

Prove that: sin36^0=(sqrt(10-2sqrt(5)))/4 .

Prove that, cos18^(@)-sin18^(@)=sqrt(2)sin27^(@)

Prove that cos18^(@)-sin18^(@)=sqrt(2)sin27^(@) .

Solve (sqrt(5)-1)/(sin x)+(sqrt(10+2sqrt(5)))/(cos x)=8,x in(0,(pi)/(2))