SOLUTION: Using the standard window settings, Emily graphed y=x^3+3x^2-x-3 on her graphing calculator. She then used her graph to correctly solve the inequality x^3+3x^3>- x+3. What is her s

Algebra ->  Graphs -> SOLUTION: Using the standard window settings, Emily graphed y=x^3+3x^2-x-3 on her graphing calculator. She then used her graph to correctly solve the inequality x^3+3x^3>- x+3. What is her s      Log On


   

Question 309091: Using the standard window settings, Emily graphed y=x^3+3x^2-x-3 on her graphing calculator. She then used her graph to correctly solve the inequality x^3+3x^3>- x+3. What is her solution.
Found 2 solutions by stanbon, Fombitz:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Using the standard window settings, Emily graphed y=x^3+3x^2-x-3 on her graphing calculator. She then used her graph to correctly solve the inequality x^3+3x^2 >- x+3. What is her solution.
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Ans: x > 0.7693
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graph%28400%2C300%2C-10%2C10%2C-10%2C10%2Cx%5E3%2B3x%5E2%2C-x%2B3%29
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Cheers,
Stan H.
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Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
I think you mean
x%5E3%2B3x%5E2%3E-x%2B3
which equates to
x%5E3%2B3x%5E2%2Bx-3%3E0
So look for the intervals when the function is greater than zero because then it satisfies the inequality,
x%5E3%2B3x%5E2%3E-x%2B3
.
.
.

The red line is the original function, x%5E3%2B3x%5E2%2Bx-3.
The green line is x%5E3%2B3x%5E2.
The blue line is -x%2B3.
When the red line is above zero is equal to when the green line is above the red line.
The x value that corresponds to when the inequality holds is,
x%3E0.7693