I really need help with these practice questions please.

2. Calculate the limit: lim - 1 x-122 -l. (a) Calculate the limit: hm h where z # 0 is a non-zero number. (b) Which step in your calculation above will no longer be applicable if m = 0? 3. The limit definition of the dervative states that: mtan = lim f(ath) - f(a) h is the slope of the tangent to y = f(x) at (a, f(a)) (a) Write out the formula for mtan applied to f(x) = vx + 8 and a = 1. (b) Compute the slope mtan of the tangent line at a = 1. (c) Write the equation y = mx + b of the tangent line to y = vx + 8 at (1, 3)