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#1 2010-03-15 16:29:06
- taylor_2009
- Member
- Registered: 2010-01-25
- Posts: 28
Find the x-coordinates on the curve with a horizontal tangent line?
Find the x-coordinates of all points on the curve y=(-x²+10x-21)³ with a horizontal tangent line.
I got y'=3(-x²+10x-21)²(-2x+10) for the derivative but I am not sure if that is right. Once I have the right derivative I just set the derivative equal to 0 and solve for x right? When I solved I got x=3,7 but MyMathLab told me I was wrong.
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#2 2010-03-15 16:41:21
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Find the x-coordinates on the curve with a horizontal tangent line?
Hi taylor;
Yes, that is the correct derivative.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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