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

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

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Given,
`sin(36)^@`
we know , `sin(2A)=2sinAcosA`
`=2sin(18)^@cos(18)^@`
putting the values of `sin(18)^@` and `cos(18)^@`
`=2(sqrt(5)-1)/4(sqrt(10+2sqrt(5))/4)`
`=sqrt((sqrt(5)-1)^2(10+2sqrt(5)))/8`
...
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