Derivatives help y = x^(2)-2x+6 & y = square root of x?

Question

I'm supposed to use the limit definition of derivative to find the derivative of each problem... Now I know what the limit definition is but I don't know what to do with it. :[

Here's two of them;

y = x^(2)-2x+6 & y = square root of x

Please help if you can.

Answer 1

y do u need to no that  

Answer 2

ii am soo smart ! and im soo good at matH! like omg awesome ! amazing ! incredible !!

[ wiink,wiink]

Answer 3

if youre so smart help her stupid.

Answer 4

wen doing dervs easy way...

x^2 take the 2 down and subtract 1

so, 2x^1

-2x = just -2

and 6= 0

so 2x-2

square root of x means x ^(1/2)

again take 1/2 down and subtract one

so, (1/2)x^ (-1/2)