I'm trying to find limits for 2 situations.

1. lim x->a

f(x)-f(a) if f(x)=x^2+4 gave me lim x ->a = 2a

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x-a

2. lim x->a

f(x)*(x^3-a^3) if f(x)=a^3 and g(x)=a^2 so I got lim x->a = 2a^2(a+1)

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(x-a)*a^2

My main concern is that so far in every situation where we had a letter instead of a number we could get rid of the letters eventually and get a number.

I'm wondering if the answers are correct and if not what might be the correct answer and/or steps to get there.

Thank you.