Ok, they tell me tofind a and b so that the function:(adsbygoogle = window.adsbygoogle || []).push({});

f(x)= *Root(2-x^2) if -root(2)<=x<=1

*x^2 + ax + b if x>1

has derivative at 1

I got that the condition for this graph to be continous at 1 is a+b=0

And I moved to check out the derivative stuff:

When x->1+, the derivative is 0

But when 1->1-, igot stuck:

lim (x->1-) of [f(x)-f(1)]/(x-1) = lim (x->1-) of (x^2+ax+b-1)/(x-1). So how should I move on?

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# Homework Help: Derivative: in trouble.

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