Need help in ap calculus!

Need help in AP calculus!!!?
Let f(x) = x^2 for x ≤ 3 and
Ax + B for x > 3
a) use the definition of the derivative to find A and B so that f '(3) exists. Justify your answer
b) Does f ' ' (3) exist? Explain.
Thanks guys hope to hear good answer from you guys.
Asked Oct 05, 2011
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Answered Oct 06, 2011

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