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Prove that: sin^2 24^0-sin^2 6^0=(sqrt(5...

Prove that: `sin^2 24^0-sin^2 6^0=(sqrt(5)-1)/8`

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consider the `LHS sin^2( 24)^@– sin^2 (6)^@`
We know that, `sin (A + B) sin (A – B) = sin^2A – sin^2B `
so,
`sin^2( 24)^@ – sin^2 (6)^@`
=` sin (24^@ + 6^@) xx(sin 24^@ – 6^@) `
= `sin 30^@ xx sin 18^@ `
= `sin 30^@ xx (sqrt5 – 1)/4`
= `1/2 × (sqrt5 – 1)/4 `
...
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  2. What is the value of cos36^@ .

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