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Sooo confused...
given that y=sin^-1 (x)
a. state dx/dy and show that dy/dx = 1x(1-x^2)^-1/2
b. Expand (1-x^2)^-1/2 giving first 2 terms
c. find cubic approximation for sin^-1(x)
d. subsituting x=root3/2 into part c. find k if pi= k x root3

WHAAAT?
(Original post by LittleLucy)
Sooo confused...
given that y=sin^-1 (x)
a. state dx/dy and show that dy/dx = 1x(1-x^2)^-1/2
b. Expand (1-x^2)^-1/2 giving first 2 terms
c. find cubic approximation for sin^-1(x)
d. subsituting x=root3/2 into part c. find k if pi= k x root3

WHAAAT?
y=sin^-1 (x)
In the above expression, take sin as the function of both sides.
Now you will get, siny=x.
Now use implicit differentiation to find dy/dx.
Then replace y in the dy/dx expression by sin^-1(x).

Can you do it till here?
Last edited by raheem94; 22-02-2012 at 20:54.
(Original post by raheem94)
y=sin^-1 (x)
Multiply both sides of the above expression by sin.
Now you will get, siny=x.
Now use implicit differentiation to find dy/dx.
Then replace y in the dy/dx expression by sin^-1(x).

Can you do it till here?
wut?
(Original post by electriic_ink)
wut?
I think i should have written it as take sin as the function of both sides, right?
(Original post by raheem94)
I think i should have written it as take sin as the function of both sides, right?
Yeah.
(Original post by electriic_ink)
Yeah.
Thanks for correcting me.

Actually no one has taught me this, i self-study maths, so i often make such type of mistakes.

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Last updated: February 22, 2012
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