differentiate : sqrt(16-x^2).. i forgot.. (1 Viewer)

[underthesun]

seems that i've been bludging, but how do you differentiate:

y = sqrt(16-x^2)

sqrt is square root of by the way.

i did get the right answer by implicitly differentiating
y^2 = 16 - x^2

but is there any way other than implicit differentiation?

looks like i have shown myself a sign of alzheimer's disease..

 

[Harimau]

Originally posted by underthesun
seems that i've been bludging, but how do you differentiate:

y = sqrt(16-x^2)

sqrt is square root of by the way.

i did get the right answer by implicitly differentiating
y^2 = 16 - x^2

but is there any way other than implicit differentiation?

looks like i have shown myself a sign of alzheimer's disease..

Use the chain rule.

dy/dx= (1/2).(2x).(16-x^2)^(-1/2)
dy/dx= x/[sqrt(16-x^2)]

 

[schooly]

Re: Re: differentiate : sqrt(16-x^2).. i forgot..

Originally posted by Harimau


Use the chain rule.

dy/dx= (1/2).(2x).(16-x^2)^(-1/2)
dy/dx= x/[sqrt(16-x^2)]

Umm. shouldnt that be:
dy/dx= (1/2).(-2x).(16-x^2)^(-1/2)
since derivative of 16-x^2 = -2x ?

 

[Harimau]

Re: Re: Re: differentiate : sqrt(16-x^2).. i forgot..

Originally posted by schooly




Umm. shouldnt that be:
dy/dx= (1/2).(-2x).(16-x^2)^(-1/2)
since derivative of 16-x^2 = -2x ?

Whoops My bad