[SPAM] [obm-l] tangente ao gráfico

["Tio Cabri st" <ilhadepaqueta@xxxxxxxxxx>]

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Bom dia.
Desejo a todos boas festas e um feliz 2008.

Sei que talvez não seja um bom dia para postar algo. Mas...
Estou precisando de ajuda (só uma luz já é o suficiente) no seguinte
exercício:

Determinar todos os pontos (a,b) de R2, tais que por (a,b) passem duas retas
tangentes ao gráfico de f(x)=x^2.

Resposta: (a,b) tal que b<a^2

Abraços
Cabri


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