" (24) prove that "4(cos^(3)16+sin^(2)20)=3(cos10+sin20)

Show that 4(cos^3 10^@+sin^3 20^@)=3(cos10^@+sin20^@)

i) Prove that: cos^(3)2A+3cos2A = 4(cos^(6)A-sin^(6)A) ii) Prove that: 4(cos^(3)10^(@) + sin^(3)20^(@)) = 3(cos10^(@)+sin20^(@))

Prove that, 4 (cos^(3) 10^(@) + sin^(3) 20 ^(@))=3 (cos 10^(@) + sin 20^(@))

Prove that 4(cos ^(3) 10^(@) + sin ^(3) 20^(@)) = 3 ( cos 10^(@) + sin 20^(@)).

Prove the following identity: 4(cos^(3)10^(0)+sin^(3)20^(@))=3(cos10^(0)+sin20^(@))

Prove that (cos20^(@)-sin20^(@))/(cos20^(@)+sin20^(@))=tan 25^(@)

Prove that :(cos20^(@)-sin20^(@))/(cos20^(@)+sin20^(@))=tan25^(@)

Prove that, (cos 20^(@) + sin 20^(@))/(cos 20^(@) - sin 20^(@)) = tan 65^(@)

Prove the following 4(cos^(3)10^(@)+sin^(3)20^(@))=3(cos10^(@)+sin20^(@))

Prove that, (cos30^(@) - sin 20^(@))/(cos 40^(@) + cos20^(@)) = 4/sqrt3 cos40^(@) cos 80^(@)