Question

Find dy for y= sqrt(x^2 +4)

Answer 1

you mean find dy/dx (derivative) ??

Answer 2

No it says dy ... idk if its a misprint. That's why I'm really conused.

Answer 3

they probably mean dy/dx (the first derivative). Do you know how to solve for that?

Answer 4

find dy/dx
whatever you get,
multiply it by dx
to get dy

Answer 5

@hartnn is this implicit differentiation by any chance?

Answer 6

you can do this without knowing implicit diff

Answer 7

Yes and second derivative stuff

Answer 8

this mainly requires chain rule, you know what is it ?

Answer 9

Yes I do

Answer 10

so, what is derivative of sqrt x ?

Answer 11

@hartnn whats the distinguishing difference of 'dy' apposed to 'dx'? and not dy/dx?

Answer 12

difference ?
dy is a small change in 'y'
dx is a small change in 'x'
dy/dx is the slope of curve y
basically you can separate the differentials.
dy/dx =....., then dy = ..... dx

Answer 13

jazzie, if you know derivative of sqrt x and chain rule, you'll be alble to solve this.

Answer 14

*able

Answer 15

Hey, @hartnn ! I'm attempting to solve this problem now.
What would my steps be?

y=(x^2+4)^(1/2)
dy/dx = (1/2)(2x)(x^2+4)^(-1/2)
dy/dx = x/[(x^2+4)^1/2]
dy = x/[(x^2+4)^1/2] dx
Is that it?

Answer 16

yup! good work :)

Answer 17

Thanks! :D