Question

Find all values of x for which the function is differentiable for y = sin x - x cos x.

Answer 1

y'=Cosx-(x*(-Sinx)+Cosx)

Answer 2

y' = Cosx + x*Sinx - Cosx = x*Sinx

Answer 3

that's a continuous function, so y is differentiable for all x

Answer 4

Okay, thank you so much!

Answer 5

How did you find y' though?

Answer 6

y' = derivative of y

Answer 7

y = sin x - x cos x.
Derivative of Sin x is Cos x
To find the derivative of x*Cosx, use the product rule

Answer 8

Oh okay. Thanks!

Answer 9

(f*g)'=f*g'+g*f'

Answer 10

and that's the product rule if ur wondering

Answer 11

Thanks :).

Answer 12

How would you do it for y = \[\sqrt{(x-1)/(1+x ^{2})}\]