Steps to finding the limit
Plug in
Simplify
Then plug bigger and smaller numbers in
The limit is infinity when…
A small number is over a huge, exponential number
The function has a vertical asymptote (x-# in the denom)
The func is exponential
Jump function
The numbers in a piecewise approach the same limit but are different
Limit DNE
How to tell when the function approaches the limit at different spots
Left hand and right hand limits
Plug in numbers bigger and smaller than the limit
If they match, the limit exists and its the given number
The limit does not exist when
Right hand limit does not match left hand limit
Function is sin or cosine
If it jumps
When you see an absolute value…
Plug in pos and neg numbers
When limit approaches infinity…
Degrees of leading coefficients
n<d -> 0
n=m -> ratio of leading coefficients
n>d infinity or negative infinity
Limit with infinity with VA in bottom
Approach a from the left and right, will either be neg or pos infinity or DNE if they don’t match
1/x; x=0 lim DNE
1/x^2 x=0 lim pos infinity
Sin x/x=
1
The limit exists as long as (GRAPH)…
The limit has a line of the left and right, doesn’t matter if there is a hole
The limit doesn’t exist if (GRAPH)…
The limit doesn’t match on the left and right
The graph is continuous if…
There’s no holes
There’s lines on the left and right
No jumps
Horizontal asymptotes
n<d, y=0
n=d, L.C of n/L.C of d
n>d, none
How do you find EBM
Subtract the powers and keep the numbers in front the same
How do you find left and right EBM
Which ever grows quicker on the left and right.
Tangent line
Find the IROC
Find x, f(x)
Plug into point slope
Normal line
Find the tangent
Find the negative reciprocal of the tangent
Use the same points
Use point slope
How do you find the average R.O.C
Plug in x1 and x2 to get y1 +y2
x2-x1/y2-y1
Instant R.O.C
Use f(x+h) - f(x)/h
Plug in x to to x+h and f(x)
How do you find the secant line
Plug in given x’s to the equation
Find slope
Plug into point slope
Left hand and right hand limit of a piecewise
Find the one that is the smallest, plug in numbers smaller
Find the one that is the biggest
plug in numbers bigger
If they are equal, the lim exists