Simple Differentiation .. (1 Viewer)

[shinji]

lol. well to me it's not simple.

Just doing Pastpapers:
Ascham School; 1993 3u paper.

Differentiate:
e^{cosec x}

 

[SoulSearcher]

d/dx e^{cosec x} = -cosec x * cot x * e^{cosec x}
I'd show that the derivative of cosec x is -cosec x * cot x, but I'm lazy today

 

[shinji]

yeah .. that's the answer.
but i don't know how to get to that. haha

man.. ur too smart to be a prelim'r <_<""
are u like accelerating maths? =/

 

[Riviet]

Use the chain rule:
let u=cosecx, then
d/dx(e^u)=d/du.(e^u) x du/dx

 

[shinji]

BAH!
-_-"" thx ! lol

 

[SoulSearcher]

Well to show that d/dx (cosec x) = -cosec x * cot x,
let y = cosec x
= 1/sin x
dy/dx = -1/sin²x * cos x
= -cos x/sin²x
= -cosec x * cot x

And yes, I'm accelerating extension 1 maths this year, done the 2 unit maths HSC exam last year.

 

[housemouse]

You just memorise the derivative of cosecx dont you?