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If x+ sqrt(15)=4, then x+1/x= 2 (b) 4...

If `x+ sqrt(15)=4,` then `x+1/x=` 2 (b) 4 (c) 8 (d) 1

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Solution:
`=>x+\ sqrt(15)=4,`
`=>x=4-sqrt(15)`
`=>1/x=1/4-sqrt(15)`
`=4+sqrt(15)/16+15`
`=4+sqrt(15)`
`x+1/x=4-sqrt(15)+4+sqrt(15)`
`=8`
Hence the correct option is `(c)`
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