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Question
Use the mirror equation to show a convex mirror always produces a virtual image independent of the location of the object ?
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Solution
A convex mirror
f > 0; u < 0 (always)
Case I |u| > |f|

We know,
`v =(fu)/(u-f)`
`fu <0 and f-u<0`
`=> v>0 ` virtual image
Case `2|u|<|f|`

`v=(fu)/(u-f) fu<0`
`=> u> 0 u-f<0`
Hence, at all the positions convex mirror will form a virtual image.
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