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Discussion Response Post to: f(x+y)=f(x)f(y) ,,,,f(5)=2,,,f'(0)=3,,,f'(5) is what

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22 May 2008 23:05:43 IST

Subject: Re:f(x+y)=f(x)f(y) ,,,,f(5)=2,,,f'(0)=3,,,f'(5) is what

karthik2007 (3733)

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Just use the definition for derivative of a function. We have, $F'(0) = \mathop{\lim}\limits_{{h} \to {0}} \frac{F(h) - F(0)}{h}$

and $F'(5) = \mathop{\lim}\limits_{{h} \to {0}} \frac{F(5)F(h) - F(5)}{h}$

In the second equation, write F(5) = F(5+0), and then use the function definition. You will get F'(5) = F'(0) x F(5) = 2x3 = 6.

Will nip in at times to solve problems :)

this reply: 5 points (with 1 Olaaa!! Perrrfect answer.

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