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Find lim x→3 sqrt 2x+3-sqrt 3x/ x^2-3x. you must show your work or explain your work in words plsss I need help

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I'm assuming the limit is supposed to be


\displaystyle\lim_(x\to3)(√(2x+3)-√(3x))/(x^2-3x)

Multiply the numerator by its conjugate, and do the same with the denominator:


\left(√(2x+3)-√(3x)\right)\left(√(2x+3)+√(3x)\right)=\left(√(2x+3)\right)^2-\left(√(3x)\right)^2=-(x-3)

so that in the limit, we have


\displaystyle\lim_(x\to3)(-(x-3))/((x^2-3x)\left(√(2x+3)+√(3x)\right))

Factorize the first term in the denominator as


x^2-3x=x(x-3)

The
x-3 terms cancel, leaving you with


\displaystyle\lim_(x\to3)(-1)/(x\left(√(2x+3)+√(3x)\right))

and the limand is continuous at
x=3, so we can substitute it to find the limit has a value of -1/18.

User Tbuehlmann
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