C=13290+13290(.055)+125=$14145.95<span>
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the main formula is </span>(cd)(x)=c(x).d(x) <span>
If c(x) = 4x – 2 and d(x) = x2 + 5x
so </span> (cd)(x) = (4x – 2)(x2 + <span>5x)=4x^3+20x²-2x²-10x=4x^3+18x²-10x
so the answer is A: </span><span>4x^3+18x²-10x</span><span>
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The amplitude of this function is 4/5. Be sure you understand why that is so.
