Cracking The Ap Calculus ab Exam 2018

Example 1: Find x^2.

The approach is simple: Plug in 5 for x, and you get 25.

Example 2: Find x^3.

Here the answer is 27.

There are some simple algebraic rules of limits that you should know. These are

kf(x)   =   k f(x)

Example: 3 x^2 = 3 x^2 = 75

If   f(x)   =   L 1     and  g(x)   =   L 2 ,   then        [f(x)   +   g(x)]   =   L 1     +   L 2

Example: [x^2 + x^3 ] = x^2 + x^3 = 150

If   f(x)   =   L 1     and  g(x)   =   L 2 ,   then        [f(x)   ·   g(x)]   =   L 1     ·   L 2

Example: = = 52

Example 3: Find (x^2 + 5x).

Plug in 0, and you get 0.

So far, so good. All you do to find the limit of a simple polynomial is plug in the number that the variable
is approaching and see what the answer is. Naturally, the process can get messier—especially if x
approaches zero.