How do you differentiate this? (2 Viewers)

[Prawnchip]

y = x all over the sqrt(x^2 + 1)

How do you know which is the best rule to use? Because you can use both product and quotient rule in this eg :S
Thanks!!

 

[ataratar]

there is no 'better' rule to use, you can use either! personally i would use quotient rule just cos i hate negatives but its completely fine to do either

 

[HSC2014]

Use the rule that you are most comfortable and fastest with

 

[chaosflaws]

Quotient rule is the straightforward way. Transforming it into a product and then doing product rule gives you exactly your quotient rule formula anyway:

y = f(x) * (g(x))^(-1)
dy/dx = f'(x) * (g(x))^(-1) + f(x) * g'(x) * (-1) * (g(x))^(-2)
dy/dx = f'(x) / g(x) - f(x) * g'(x) / (g(x))^2

Common denominator:

dy/dx = (f'(x) * g(x) - f(x) * g'(x)) / (g(x))^2

 

[Prawnchip]

I figured it out! thanks for the help guys ^_^