SOLUTION: sketch a cubic function (third degree polynomial function y=p(x) where p(x)>0 on the intervals (-infinity,3) and (5,8)
Then determine a formula for your function
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-> SOLUTION: sketch a cubic function (third degree polynomial function y=p(x) where p(x)>0 on the intervals (-infinity,3) and (5,8)
Then determine a formula for your function
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Question 1113424: sketch a cubic function (third degree polynomial function y=p(x) where p(x)>0 on the intervals (-infinity,3) and (5,8)
Then determine a formula for your function Answer by greenestamps(13198) (Show Source):
The given information about the intervals on which the function value is positive tells us that the function value changes sign at 3, 5, and 8; that means those are the three roots.
So the function is of the form .
For positive values of the coefficient a, the function value will be positive for large positive values of x. Since the function value is negative for large values of x, the coefficient a must be negative.
The given information allows us to choose any negative value for a; -1 is easiest. So a function that satisfies the given requirements is .
