Problem Calculating a limit with a square root, i'm stuck

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The limit in question is for the expression (9-t)/(3-√t) as t approaches 9. Initial attempts to simplify by multiplying by the conjugate led to confusion about the limit's existence. However, factoring the numerator as a difference of squares provides a clearer path to the solution. The limit does exist and can be evaluated correctly through this method. Proper simplification techniques are crucial for resolving limits involving square roots.
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Problem Calculating a limit with a square root, I'm stuck :(

Homework Statement




The limit is equation 9-t / 3-sqrt(t) as t approaches 9

I'm stuck on the how to simplify this?

Thanks for any help.


Homework Equations





The Attempt at a Solution

 
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Try multiplying by (3+√t)/(3+√t)
 


I discovered that that is the conjugate and I came out with this:

27-6sqrt(t)-tsqrt(t)
----------------
9-t

So in other words, that limit does not exist. Is that right?
 


The limit does exist. Instead of multiplying by the conjugate over itself, just factor the numerator, treating it as the difference of two squares.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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