SOLUTION: f(x)=13x3+13x4-3x findf(-6)

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Question 23080: f(x)=13x3+13x4-3x
findf(-6)
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29=13x%5E3%2B13x%5E4-3x
find f(-6)

This is a special notation called "functional notation" that means that if
f%28x%29=13x%5E3%2B13x%5E4-3x, then to find f(-6) you just substitute -6 in place of all the x's in the formula, and calculate it! In this case, you might want to use a calculator, unless your teacher says you need to do it all in your head!!
f%28x%29=13x%5E3%2B13x%5E4-3x
+f%28-6%29=+13%2A%28-6%29%5E3+%2B+13%2A%28-6%29%5E4+-3%28-6%29
+f%28-6%29+=+13%2A%28-216%29+%2B+13%2A1296%2B18
+f%28-6%29+=+-2808+%2B16848+%2B18
+f%28-6%29=14058

It's even easier, especially for a problem with large numbers and huge arithmetic, to solve this one with a graphing calculator!!! If anyone has a TI84, TI83, or TI86, try graphing y1=13x%5E3%2B13x%5E4-3x. Actually you don't even care what the graph looks like. Just go to TRACE, and go to x=-6. The value of y when x=-6 is the value we are looking for, 14058 FINAL ANSWER!!

R^2 at SCC