http://www.freeimagehosting.net/7kphi
yup I was too lazy so I took a screenshot of my hw and uploaded it, please take a look this is the ONLY problem that I cannot do by myself like wtf its so hard. I know you start doing that dy/dx thing but then when you subsitute I get lost, like idk what you substiute for what
Anywho who got all the correct answers (both x values) -- why are there two x's not y's? Confused. And fill in the blanks at the end..if anyone can get all correct answer youll make me one very happy girl and get 10 points for you ;) thanks x1000!
yup I was too lazy so I took a screenshot of my hw and uploaded it, please take a look this is the ONLY problem that I cannot do by myself like wtf its so hard. I know you start doing that dy/dx thing but then when you subsitute I get lost, like idk what you substiute for what
Anywho who got all the correct answers (both x values) -- why are there two x's not y's? Confused. And fill in the blanks at the end..if anyone can get all correct answer youll make me one very happy girl and get 10 points for you ;) thanks x1000!
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Hey Purr
We are given this equation, 19x² + xy + 3y = 2, which is not too difficult to rewrite as "y = something in x," so that's what I'll do:
y = (2 - 19x²)/(x + 3)
Below is the derivative:
dy/dx = - (19x² + 114x + 2)/(x² + 6x + 9)
Set this equal to zero, and at x = - 3 ± 13/√19, you have the two horizontal tangents. Here are the coordinates of these points:
(-0.01759546, 0.668627) and (-5.98249454, 227.331372532)
Here's what the graph looks like, if you are interested:
http://www.google.com/#hl=en&safe=active…
Easy, peezy, nice and sleazy!
alice
P.S.: You could also solve for dy/dx implicitly; you will get the same answer in the end, of course. See the sources below for how that works. Ciao!
alice
We are given this equation, 19x² + xy + 3y = 2, which is not too difficult to rewrite as "y = something in x," so that's what I'll do:
y = (2 - 19x²)/(x + 3)
Below is the derivative:
dy/dx = - (19x² + 114x + 2)/(x² + 6x + 9)
Set this equal to zero, and at x = - 3 ± 13/√19, you have the two horizontal tangents. Here are the coordinates of these points:
(-0.01759546, 0.668627) and (-5.98249454, 227.331372532)
Here's what the graph looks like, if you are interested:
http://www.google.com/#hl=en&safe=active…
Easy, peezy, nice and sleazy!
alice
P.S.: You could also solve for dy/dx implicitly; you will get the same answer in the end, of course. See the sources below for how that works. Ciao!
alice
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Seems like three's more than just ONE you aren't interested in doing for yourself.