Evaluate the following limits:



Since the form is indeterminant



Method 1: factorization



Since a3 + b3 = (a + b)(a2 + b2-ab) & a2-b2 = (a + b)(a-b)




= (-1)2 + (1)2 - (-1)


= 3


Method 2: By L hospital rule:


Differentiating numerator and denominator separately:





= 3(-1)2


= 3


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