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Prove that: cos^2 48^0-sin^2 12^0=(sqrt...

Prove that: `cos^2 48^0-sin^2 12^0=(sqrt(5)+1)/8`

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Given,
`=>cos^2 48^@-sin^2 12^@`
we know that,
`cos^2A-sin^2b=cos(A+B)cos(A-B)`
`=>cos(48+12)^@cos(48-12)^@`
`=>cos (60)^@cos(36)^@`
`=>(1/2)((sqrt(5)+1)/4)`
`=>((sqrt(5)+1)/8) `
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