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`M=(h_(2))/(h_(1))" …..(i)"`
`M=(v)/(u)" …..(ii)"`
From equations (i) and (ii) what is the relation between `h_(1), h_(2), u and v` ?

Explanation

From the given equations, we can say that,
`(h_(2))/(h_(1))=(v)/(u)`
According to Cartesian sign convention, for concave lens, `h_(2) and h_(1)` are always positive while v and u are always negative.
`therefore" "(+h_(2))/(+h_(1))=(-v)/(-u)`
Similarly, for convex lens, when object is placed within the focal length, `h_(2) and h_(1)` are positive while v and u are negative.
`therefore" "(+h_(2))/(+h_(1))=(-v)/(-u)`
For all other positions of object, `h_(2) and u` are negative while, `h_(1) and v` are positive.
`therefore" "(-h_(2))/(+h_(1))=(+v)/(-u)`