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Maths frustration

Hey,

i am beyond frustration with differentiating quotient agh.
Could anyone please help with the following:

Differentiate with respect to x
x/(x+1) ^1/2

Thanks
Reply 1
Avatar for Alexion
Alexion
17
Try instead using the product rule on x(x+1)-1/2 and see if that gets you anywhere :cute:
Original post by lailapianai
Hey,

i am beyond frustration with differentiating quotient agh.
Could anyone please help with the following:

Differentiate with respect to x
x/(x+1) ^1/2

Thanks


Use the quotient rule. Let uv=x(x+1)12\frac{u}{v} = \frac{x}{(x+1)^\frac{1}{2}} you'll have to find v′v' using the chain rule, as (x+1)12(x+1)^\frac{1}{2} is a composite function.
Reply 3
Avatar for math42
math42
20
If the quotient rule is not too fun for you, product rule is perfectly valid (quotient rule is just an application of the product rule after all) and maybe faster. What have you tried?
Reply 4
Avatar for oShahpo
oShahpo
20
Simply put,
1) mutliply the bottom bit by the derivative of the top bit then minus (the product of the top bit and the derivative of the bottom bit)
2) divide the whole expression by the bottom bit squared.
Original post by Alexion
Try instead using the product rule on x(x+1)-1/2 and see if that gets you anywhere :cute:


I tried this and i still cant get the answer :frown:
I got -1/2x (x+1)^1/2 /(x+1)^1/2
Original post by 1 8 13 20 42
If the quotient rule is not too fun for you, product rule is perfectly valid (quotient rule is just an application of the product rule after all) and maybe faster. What have you tried?


I tried using the product rule instead and got this
-1/2x (x+1)^1/2 /(x+1)^1/2
Reply 7
Avatar for Alexion
Alexion
17
Original post by Alexion
Try instead using the product rule on x(x+1)-1/2 and see if that gets you anywhere :cute:


Original post by lailapianai
I tried this and i still cant get the answer :frown:
I got -1/2x (x+1)^1/2 /(x+1)^1/2


Well if we take the two sections we get

(x+1)-1/2 * -(1/2)x(x+1)-3/2

from the product rule. Try simplifying that.

Remember the second term if you're using the product rule is (x+1)-1/2 not (x+1)1/2
(edited 7 years ago)
Original post by Alexion
Well if we take the two sections we get

(x+1)-1/2 * -(1/2)x(x+1)-3/2

from the product rule. Try simplifying that.

Remember the second term if you're using the product rule is (x+1)-1/2 not (x+1)1/2


Thanks

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