How to use the - definitionto solve (a)

and also solve the question (b) and (c)

0 using the denition centinuous, the one-variable square root __ of continuous functions is continuous. ' ' f is not differentiable at 0. 'Hint: Observe til: erentiable at 0. The numerator' 1n (1) with x0 Hm lell Df(0)(X)'=~ xsxo - uxu ' sector iniR2, using (2) show that D f(0)(\\?') ' 11 (pick any v; what IS D f (O)(v)'7) ' x. -- ) Denef: UHwby 2'2