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How can i solve this :( thanks for your help. I don't know how to calculate the limit of this equation :(( I tried and my solution is =1 while the answer of this problem is 0.

How can i solve this :( thanks for your help. I don't know how to calculate the limit-example-1
User TwistedSim
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1 Answer

3 votes

Answer:

use l'Hopital's rule

Explanation:

The expression given evaluates to 0/0 at x=1, so l'Hopital's rule can be used to find the limit. This requires you to differentiate the numerator and denominator separately and find the ratio of the derivatives at x=1.

n = √(2x -1) +x^2 -3x +1

n' = 1/√(2x -1) +2x -3 ⇒ 1/√(2-1) +2 -3 = 0 . . . at x=1

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d = ∛(x -2) +x^2 -x +1

d' = 1/(3∛((x-2)^2)) +2x -1 ⇒ 1/(3∛1) +2 -1 = 4/3 . . . at x=1

Then the limit is ...

n'/d' = 0/(4/3) = 0 . . . . limit as x approaches 1

_____

A graphing or spreadsheet calculator can be helpful. The attached graph is expected to have a hole at x=1, but does not. Whereas numerator and denominator are both zero at x=1, the calculators seems perfectly happy to evaluate their ratio there.

How can i solve this :( thanks for your help. I don't know how to calculate the limit-example-1
User AtiqGauri
by
4.7k points