Problem

Solve the inequality f(x)>0, where f(x)=x2(x+3), by using the graph of the function.
The solution set for f(x)>0 is (Type your answer in interval notation.)

Answer

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Answer

The solution set for the inequality f(x)>0 is (3,0)(0,)

Steps

Step 1 :Given the inequality f(x)>0, where f(x)=x2(x+3), we are looking for the values of x where the function f(x) is positive.

Step 2 :The function f(x)=x2(x+3) is a cubic function and its graph will cross the x-axis at the roots of the equation f(x)=0. The roots of the equation are x=0 and x=3.

Step 3 :We can divide the number line into three intervals based on these roots: (,3), (3,0), and (0,). We can then test a number from each interval to see if the function is positive or negative in that interval.

Step 4 :For the interval (,3), we can test x=4. For the interval (3,0), we can test x=1. For the interval (0,), we can test x=1.

Step 5 :The function f(x) is negative for x in the interval (,3) and positive for x in the intervals (3,0) and (0,).

Step 6 :Therefore, the solution set for the inequality f(x)>0 is (3,0)(0,).

Step 7 :The solution set for the inequality f(x)>0 is (3,0)(0,)

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