Re: question about the 86 and the 89
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Re: question about the 86 and the 89
Maybe I am wrong here, but since x is a constant, the equation on the right
side of the equality will go to zero since you are taking the fifth
derivative, and,
since you will subtract the quantity (y^9 -6x^3) from the right side to set
the
whole thing to zero, the 6x^3 is zero after the first derivative. So, all
you have
to do is get the fifth derivative of y^9. Am I right or wrong here?
59(x^2)(y^4)-(y^9-6x^3)=0
x=56
59(56^2)y^4-y^9-6(56^3)=0
3136y^4-y^9-1053696=0
d/dy(3136y^4-y^9-1053696)=12544y^3-9y^8
d/dy(12544y^3-9y^8)=37632y^2-72y^7
d/dy(37632y^2-72y^7)=75264y-504y^6
d/dy(75264y-504y^6)=75264-3024y^5
d/dy(75264-3024y^5)=-15120y^4
or more simply (9*8*7*6*5)y^4=0, since the other parts of
the equation go to zero by the time you take the
fifth derivative.
At 02:34 Silent 10/17/98 +0200, you wrote:
>>> "Find the tanget line for the fifth derivative of
>> y^9-6x^3=59(x^2)(y^4) when
>>> x=56."
>
>>Ehm .. do you need a calculator at all to solve this problem . Looks pretty
>> simple to me.
>
>Anyway, how do you solve this w/wo a calculator... I see no way to solve for
>y (and Derive could not do it either)
Duane M. Sikkema Jr.
soldevi@usxchange.net
References: