- #1
Nguyen Thanh Nam
- 14
- 0
Ok, they tell me tofind a and b so that the function:
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 continuous 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?
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 continuous 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?