Question 181622
f(x)=(2x^2)+4x
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When you want to find f(x)-f(a))/(x-a) (lim as x approaches a), you are saying that you want to differentiate f(x) with respect to x.
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Differentiating skill: if f(x)=ax<sup>n</sup> then f'(x)=anx<sup>n-1</sup> where f'(x) is the derivative of f(x).

f(x)=2x<sup>2</sup>+4x
f'(x)=2(2)x<sup>2-1</sup>+4(1)x<sup>1-0</sup>
f'(x)=4x-4
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That's it.
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Power up,
HyperBrain!
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