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)




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




= (√4 + 2)(4 + 4)


= (2 + 2)(4 + 4)


= 32


Method 2: By L hospital rule:


Differentiating numerator and denominator separately:





= 4(4)3/2


= 32


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