Question 100166
You are given:
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{{{f(x)=3x(2x-1)}}}
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and you are asked to find {{{f(-1)}}}
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All this means is that you start with the given function of:
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{{{f(x)=3x(2x-1)}}}
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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(-1) = 3*(-1)*(2(-1)-1)}}}
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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: {{{(2(-1)-1)}}}. Multiplying the 2 times the -1 
results in -2 and the set of parentheses then contains {{{(-2 - 1)}}}. 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(-1) = 3*(-1)*(-3)}}}
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Now on the right side multiply the 3*(-1) to get -3. With this substitution the function
becomes:
{{{f(-1) = (-3)*(-3)}}}
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Multiply out the right side. -3 times -3 is +9 and the function reduces to:
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{{{f(-1) = +9}}}
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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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