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VED1
E L-LOVELY-H math9-1 IInd 6-8-11 IIIrd 24-1-12 IVth 21-4-12 Vth 20-8-12 VIth 10-9-12

noEPk;soh dk rfDs

B'N y d/ T[uso iK fBwBso wkB d/ bJh
dy
& 0
dx
∴ – (1 + log x) y = 0 iK log x = – 1 ∵ y ≠ 0
iK –log x = 1
1 1
iK log = log e ⇒ x = .
x e
2
dy  1 dy 
+
x
j[D = – y . + (1 log ) 

dx 2  x dx 
1
x = gqfs;Ekfgs eoB s/
e
2
dy dy
= – [ey + 0], ∵ = 0
dx 2 dx
2
dy = – ey foDkswe j?. ∴ x = 1 d/ bJh cbB T[uso j?.
dx 2 e
1
∴ fBofdPN cbB ftZu x = gqfs;Ekfgs eoB s/
e
 1/e

1
1/e
T[uso wkB =  = (e) f;ZX j'fJnk j?.
1



e
log x
T[dkjoD 8H dk T[uso wkB gsk eo', id'A fe 0 < x < ∞ H
x
log x
jZb L wzB fbU y =
x

∴

dy & 0 oZyD s/, 1 log x− = 0 iK 1 – log x = 0
dx x 2
iK log x = 1 = log e, ∴ x = e
2
−
dy 2loge − 3 2 3 1
x = e T[Zs/, = = =− & foDkswe j?.
dx 2 e 3 e 3 e 3
∴ x = + e T[Zs/ cbB T[uso j? ns/
loge 1
fJ;dk T[uso wkB = = H T[Zso
e e

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