Posted by **Ifi** on Saturday, October 27, 2012 at 10:25am.

How to d/dx

y= (9+((x-9)/6)^1/5)^1/2 ?

Hope u can give me the way how to calculate it. ^^

I got 1/60 ((x-9)/6) ^ (-9/10), i think my answer is wrong because i check at wolfram website the ans is differrent from mine (sorry i didn't write the ans bcus the ans is quite long and difficult to type)

- Math -
**Reiny**, Saturday, October 27, 2012 at 1:01pm
not quite ....

let u = ( (x-9)/6 )^(1/5)

then y = (9 + u)^1/2

dy/du = (1/2)(9+u)^(-1/2)

du/dx = (1/5)( (x-9)/6 )^(-4/5) (1/6)

= (1/30) ( (x-9)/6 )^(-4/5)

so dy/dx = dy/du * du/dx

= (1/2)(9 + u)^-1/2) (1/30) ( (x-9)/6 )^(-4/5)

= (1/60) (9 + ( (x-9)/6 )^(1/5)^(-1/2) ( (x-9)/6 )^(-4/5)

I suggest you check my steps for any errors, I should have written it out on paper first.

Wolfram seems to have performed some kind of complicated simplification.

How about this way:

square both sides:

y^2 = 9 + ( (x-9)/6 )^1/2 , then by implicit differentiation,

2y dy/dx = (1/2)( (x-9)/6) )^(-1/2)

dy/dx = (1/4)(√(6/(x-9) ) / y

or √6/(4y√(x-9) ) , that's not bad

- Math - hmm -
**Steve**, Saturday, October 27, 2012 at 2:45pm
not bad, but

y^2 = 9 + ((x-9)/6)^(1/5)

2y dy/dx = 1/5 ((x-9)/6)^(-4/5)

dy/dx = 1/(10y ((x-9)/6)^(4/5))

- Got me - Math -
**Reiny**, Saturday, October 27, 2012 at 2:50pm
thanks for looking after me,

rotten copy errors.

- Math -
**Ifi**, Saturday, October 27, 2012 at 9:04pm
thanks for the calculation but i think there is a mistake at implicit diff.

y^2= 9 + ((x-9)/6)^(1/5)

2y dy/dx = 1/5 ((x-9)/6)^(-4/5)) (1/6)

dy/dx = 1/60y ((x-9)/6)^(-4/5) ..... Sorryif im wrong

Btw why at wolfram the answer is

1/( 60y(-9+y^2)^4). Why is the x become y^2 and why there are no 6 and ^(4/5)?

## Answer This Question

## Related Questions

- Math - Differentiate f(x)= (8-2x)^3(x^2+1)^5. My ans is 2(8-2x)^2(x^2+1)^4(-3x^2...
- math - use implicit differentiation to find dy/dx and then d^2y/dx^2. y^2=ye^x^2...
- Math - Calculate dy/dx, (x^3)(y^7) + 16xy^6=0 My ans is (y(-16-3x^2y))/ x(96+7x^...
- Math check and question - x is a binomial random variable. (Give your answers ...
- Math check - Find the critical value for the hypothesis test, given the ...
- Science - Which resource can be recycled? A. Natural Gas B. Eggs C. Sunlight D. ...
- Statistic check - Find the critical value for the hypothesis test, given the ...
- 7th grade math (probability) - Can you check these, please? Ten cards numbered 1...
- chem - an aq. solution(NaCl) made by using 133g diluted to a total solution ...
- 8th Grade Algebra- Answer Check - Solve each system of equations, give the ...

More Related Questions