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

fJekJh^9 L T[uso ns/ fBwBso L fJZe uo

fJjBK jh fpzd{nK T[Zs/ cbB T[uso iK fBwBso j't/rk. B'N

1 d 2 y 1
j[D x = T[Zs/ dk wkB = 6. – 4 = – 2 < 0 (foDkswe)
3 dx 2 3

1
∴ cbB x = T[Zs/ T[uso j?.
3
d 2 y
ns/ x = 1 T[Zs/ dk wkB = 6.1 – 4 = 2 > 0 (XBkswe)
dx 2
fJ; soQK x = 1 T[Zs/ fBwBso j?.

1
1
1
  3  2 1 166
T[uso wkB = f  =  – 2 .  + + 6 =
3
3
   3 27
3
2
3
ns/ fBwBso wkB = f (1) = 1 – 2. 1 + 1 + 6 = 6. T[Zso
2
3
T[dkjoD 4H cbB 2x – 9x + 12x – 3, x d/ feBQK wkBK T[Zs/ T[uso iK fBwBso j?<
cbB d/ T[jBK wkBK B{z th gsk eo'.
3
2
jZb L wzB fbU fe y = 2x – 9x + 12x – 3
j[D cbB dk x d/ ;kg/y fBy/VB eoB s/
dy
2
2
= 6x – 18x + 12 = 6(x – 3x + 2) ....(1)
dx
cbB d/ T[usw iK fBT{Bsw wkB d/ bJh
dy
= 0
dx
2
2
∴ 6(x – 3x + 2) = 0 iK x – 3x + 2 = 0
iK (x – 1) (x – 2) = 0 ∴ x = 1, 2
j[D (1) dk fBy/VB eoB s/
d 2 y
= 6 (2x – 3)
dx 2
d 2 y
ns/ x = 1 d/ bJh = 6(2. 1 – 3) = – 6 fijVk foD j?.
dx 2

fJ; soQK x = 1 T[Zs/ cbB T[uso j?.
2
3
fJj T[uso wkB = 2. 1 – 9. 1 + 12. 1 – 3
= 2 – 9 + 12 – 3 = 2 T[Zso
d 2 y
j[D x = 2 d/ bJh = 6(2.2 – 3) = 6 XB j?.
dx 2
fJ; soQK x = 2 T[Zs/ cbB T[uso j?.
ns/ cbB dk fBwBso wkB
3
2
= 2.2 – 9.2 + 12.2 – 3 = 1 T[Zso

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