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The roots of the equation 4x^2-2sqrt(5)x...

The roots of the equation `4x^2-2sqrt(5)x+1=0,a r e` `sin36^0,sin18^0` (b) `sin18^0,cos36^0` `sin36^0,cos18^0` (d) `cos18^0,cos36^0`

A

`sin36^(@),sin18^(@)`

B

`sin18^(@),cos36^(@)`

C

`sin36^(@),cos18^(@)`

D

`cos 18^(@),cos36^(@)`

Text Solution

Verified by Experts

The correct Answer is:
B
`4x^(2)-2sqrt(5)x+1=0`
`therefore x=(2sqrt(5)+-2)/(8)=(sqrt(5)+-1)/(4)`
`therefore` Roots are `sin 18^(@)` and `cos36^(@)`
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