SOLUTION: Please help me solve this equation: f(x)=3x(2x-1).f(-1)=

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Question 100166This question is from textbook
: Please help me solve this equation: f(x)=3x(2x-1).f(-1)= This question is from textbook

Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
You are given:
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f%28x%29=3x%282x-1%29
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and you are asked to find f%28-1%29
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All this means is that you start with the given function of:
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f%28x%29=3x%282x-1%29
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And you plug in -1 wherever you see an x. When you do that the given function becomes:
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f%28-1%29+=+3%2A%28-1%29%2A%282%28-1%29-1%29
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Now all you have to do is to reduce the right side. Start with the last set of parentheses on
the right side. Those parentheses are: %282%28-1%29-1%29. Multiplying the 2 times the -1
results in -2 and the set of parentheses then contains %28-2+-+1%29. The two terms now inside
the parentheses then combine to give -3, and with that substitution the function reduces to:
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f%28-1%29+=+3%2A%28-1%29%2A%28-3%29
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Now on the right side multiply the 3*(-1) to get -3. With this substitution the function
becomes:
f%28-1%29+=+%28-3%29%2A%28-3%29
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Multiply out the right side. -3 times -3 is +9 and the function reduces to:
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f%28-1%29+=+%2B9
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and that's the answer you were asked to find.
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Hope this helps you to understand the problem.
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