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Let's take it from here:Doc Al said:You took the cube root of 8 (81/3) and then cubed it. Why?
The limit would be 256.Delta2 said:Yes the limit is 1/2. If we tweak the function and we make it so that f(x) is the same as before for all ##x\neq 8## but we set ##f(8)=256## what will the limit be?
Nope it will remain 1/2. For the limit we focus what happens around the point of interest but not necessarily onto the point of interest. Around 8 the tweaked function remains the same so the limit remains the same. I just introduced an artificial discontinuity in the tweaked function by setting f(8)=whatever except 1/2.nycmathguy said:The limit would be 256.
What are limits doing in a pre-calculus book, one wonders?Delta2 said:Nope it will remain 1/2. For the limit we focus what happens around the point of interest but not necessarily onto the point of interest. Around 8 the tweaked function remains the same so the limit remains the same. I just introduced an artificial discontinuity in the tweaked function by setting f(8)=whatever except 1/2.
I guess you need to be introduced to continuity and discontinuity by your textbook. If it is not done by your precalculus book, it should be done by your calculus I book.
The boundaries between calculus and precalculus are fuzzy, at least that's what Ron Larson thinks lol...PeroK said:What are limits doing in a pre-calculus book, one wonders?
A limit is a mathematical concept that describes the behavior of a function as its input approaches a certain value. It represents the value that the function approaches, or "approaches but never quite reaches", as the input gets closer and closer to the specified value.
The limit of a function can be found by evaluating the function at values close to the specified limit and observing the trend of the outputs. If the outputs approach a certain value as the inputs get closer to the specified value, then that value is the limit of the function.
Some properties of limits include the sum, difference, product, and quotient properties, which state that the limit of a sum, difference, product, or quotient of two functions is equal to the sum, difference, product, or quotient of the limits of the individual functions.
The Squeeze Theorem, also known as the Sandwich Theorem, states that if two functions have the same limit at a certain point, and a third function is between them, then the third function also has the same limit at that point. It is used to evaluate limits of functions that are difficult to evaluate directly.
Yes, a function can have a limit at a point but not be continuous at that point. This can happen if there is a "hole" or "jump" in the graph of the function at that point, or if the function is undefined at that point. In order for a function to be continuous at a point, it must have a limit at that point and the limit must be equal to the value of the function at that point.