Limits and derivatives

[kc2010]

Find the values of a such that f is continuous on all real numbers

f(x) = x + 1 if x < or = to a
x^2 if x > a

 

[stapel]

To be continuous, the two pieces must meet at x = a.

When does a[sup:1l4ye3ud]2[/sup:1l4ye3ud] equal a + 1?