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1>sin^8 x+cos^8 x=7/8+(1/8)cos6 x
2>[(sin^2 3a)/sin^2 a] - [(cos^2 3a)/ Cos^2 a] = 8cos 2a
3>[(cos^3 a - cos 3a)/cos a] + [(sin^3 a +sin 3a)/sin a]=3
1>sin^8 x+cos^8 x=7/8+(1/8)cos6 x
2>[(sin^2 3a)/sin^2 a] - [(cos^2 3a)/ Cos^2 a] = 8cos 2a
3>[(cos^3 a - cos 3a)/cos a] + [(sin^3 a +sin 3a)/sin a]=3
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