SOLUTION: Find the value of the polynomial x^3-4x when x=-2..How do I do this problem??

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Question 84723: Find the value of the polynomial x^3-4x when x=-2..How do I do this problem??
Answer by ptaylor(2198) About Me  (Show Source):
You can put this solution on YOUR website!
First, we substitute x=-2 into the polynomial and we get:
%28-2%29%5E3-4%28-2%29
Look at the first term:
%28-2%29%5E3=%28-2%29%28-2%29%28-2%29=%28%2B4%29%28-2%29=-8
Look at second term
-4%28-2%29=%2B8
Now let's put the two terms back together:
-8+8=0---------------------ans
Hope this helps----ptaylor