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anonymous
 one year ago
For what values of x does the graph of f(x) have a horizontal tangent? (Enter your answers as a commaseparated list.)
f(x) = x3 + 9x2 + x + 3
anonymous
 one year ago
For what values of x does the graph of f(x) have a horizontal tangent? (Enter your answers as a commaseparated list.) f(x) = x3 + 9x2 + x + 3

This Question is Closed

kropot72
 one year ago
Best ResponseYou've already chosen the best response.0Is this a calculus question in your course?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Yes, sorry i meant to say that.

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.2so you're looking for like... dw:1442087496186:dw something like that I assume..

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Did you try solving f ' (x) = 0

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0f ' (x) = 0 3x^2 + 18x + 1 = 0 to solve this use quadratic formula

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i tried that and i got it wrong

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.2Just complete the square.\[3x^2+18x+1=0\]\[3(x^2+6x)=1\]\[c=\left(\frac{6}{2}\right)^2 = (3)^2=9\]\[3(x^2+6x+9)=1+27\]\[3(x+3)^2=26\]

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.2Why are the 9 and 3 highlighted?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0My professor changed the original question and put them numbers instead

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.2ok lets finish the equation I was solving... let's find x. \[3(x+3)^2=26\]\[x+3 = \pm \sqrt{\frac{26}{3}}\]\[x=3\color{red}{\pm}\sqrt{\frac{26}{3}}\]

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.2That's where your error is.

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.2Do you see what I mean?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0can you write it down on paper?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0its confusing to look at it on the computer

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.2\[\boxed{\large x=3+\sqrt{\frac{26}{3}}~,~ 3\sqrt{\frac{26}{3}}}\]

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.2What you have written is \[\large x = 3\sqrt{\frac{26}{3}}~,~ 3\sqrt{\frac{26}{3}}\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Did I do this right?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I read over it and its still wrong

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0disregard the {} i did put ()

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i got it to finally work thanks you guys
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