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point (2, 3)
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Tötou deiVoi ve
 (a) TotaL derivative
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        Let 4(2,)-C du
                              da
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 Y= 20t +2 Y
 du   -2
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sinu        Ces (siny)+ cos(sinc) y
 siu
Anu =
 sinu
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 A-(34y3473)
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                                                   3