YAMT: Calculus MAT124, help solving for dy **DONE**

[Ricemarine]

Alright, so y = square root of x

Solve for delta y when x = 25.9 and x (sub 0) = 25...
Also solve for dy (derivative of y)...

So, for delta y, I just plugged in the square root of 25.9-25, which is the square root of .9. Not sure of that's right...

For dy, so far, all I got is .5(x)^-.5 * dx, I am pretty lost what to do next...

Help?
Thanks .

 

[Ricemarine]

Bumpers.

 

[Heisenberg]

dy/dx = 0.5*x^(-0.5). So dy = 0.5*x^(-0.5) * dx.

 

[Ricemarine]

Originally posted by: Heisenberg
dy/dx = 0.5*x^(-0.5). So dy = 0.5*x^(-0.5) * dx.

Do I leave it as that? and is my delta y right?
Thanks for replying at least Heisenberg

 

[Heisenberg]

Originally posted by: Ricemarine

Originally posted by: Heisenberg
dy/dx = 0.5*x^(-0.5). So dy = 0.5*x^(-0.5) * dx.

Do I leave it as that? and is my delta y right?
Thanks for replying at least Heisenberg

You could put in numbers if you want I guess, so dy = 0.5*25^(-0.5)*0.9 = 0.09
And I think your deltay should be deltay = y1 - y0 = sqrt(25.9) - sqrt(25) = 0.089.
If you think about it, those two numbers should be fairly close.

 

[Ricemarine]

Originally posted by: Heisenberg

Originally posted by: Ricemarine

Originally posted by: Heisenberg
dy/dx = 0.5*x^(-0.5). So dy = 0.5*x^(-0.5) * dx.

Do I leave it as that? and is my delta y right?
Thanks for replying at least Heisenberg

You could put in numbers if you want I guess, so dy = 0.5*25^(-0.5)*0.9 = 0.09
And I think your deltay should be deltay = y1 - y0 = sqrt(25.9) - sqrt(25) = 0.089.
If you think about it, those two numbers should be fairly close.

Ahh, ok, my deltay is wrong... But as for the dy... why is 0.9 deltax?...

Thanks again

 

[Heisenberg]

Originally posted by: Ricemarine

Originally posted by: Heisenberg

Originally posted by: Ricemarine

Originally posted by: Heisenberg
dy/dx = 0.5*x^(-0.5). So dy = 0.5*x^(-0.5) * dx.

Do I leave it as that? and is my delta y right?
Thanks for replying at least Heisenberg

You could put in numbers if you want I guess, so dy = 0.5*25^(-0.5)*0.9 = 0.09
And I think your deltay should be deltay = y1 - y0 = sqrt(25.9) - sqrt(25) = 0.089.
If you think about it, those two numbers should be fairly close.

Ahh, ok, my deltay is wrong... But as for the dy... why is 0.9 deltax?...

Thanks again

Well because the two values you were given were 25.9 and 25, so dx=0.9. I was assuming (since it's written kind of ambiguously) the point of the question was to see that deltay and dy were close since dy is just the infinitesimal limit of deltay.

 

[Ricemarine]

Originally posted by: Heisenberg

Originally posted by: Ricemarine

Originally posted by: Heisenberg

Originally posted by: Ricemarine

Originally posted by: Heisenberg
dy/dx = 0.5*x^(-0.5). So dy = 0.5*x^(-0.5) * dx.

Do I leave it as that? and is my delta y right?
Thanks for replying at least Heisenberg

You could put in numbers if you want I guess, so dy = 0.5*25^(-0.5)*0.9 = 0.09
And I think your deltay should be deltay = y1 - y0 = sqrt(25.9) - sqrt(25) = 0.089.
If you think about it, those two numbers should be fairly close.

Ahh, ok, my deltay is wrong... But as for the dy... why is 0.9 deltax?...

Thanks again

Well because the two values you were given were 25.9 and 25. I was assuming (since it's written kind of ambiguously) the point of the question was to see that deltay and dy were close since dy is just the infinitesimal limit of deltay.

Ahh ok, thanks :beer:

 

[Heisenberg]

Originally posted by: Ricemarine
Ahh ok, thanks :beer:

:beer: