## anonymous 5 years ago Multiple Choice: An equation for a tangent to the graph of y=archsin (x/2) at the origin is (a) x-2y=0 (b) x-y=0 (c) x=0 (d) y=0 (e) pix-2y=0

1. anonymous

just arcsin* btw.. hehe

2. anonymous

find the derivative then substitute 0,0

3. anonymous

derivative of arcsin is 1/(sqrt 1-x^2) btw..

4. amistre64

y = sinh^-1 y' = e^-x - e^...../2........ something..... I know the other ones :)

5. amistre64

oh...that "h" threw me. y' = 1/sqrt(1-x^2)

6. anonymous

lol !

7. anonymous

thats why i corrected him at top :P

8. amistre64

the equation to the tangent has the derivative as the slope.... 0 = f'(x)x + b

9. amistre64

yeah ;)

10. amistre64

"y=archsin (x/2) at the origin" ack!!..... it helps to read the whole thing, I get lazy and start making up my own question lol

11. amistre64

at 0,0 you get a slope of 1, so the equation of the tangent is: y = x and thats my final offer

12. anonymous

lmao! i hope u put 0,0 in the derivative!

13. amistre64

:) I think I miss placed a Dx tho.... since its got that x/2 in there ;)

14. anonymous

$1/ (\sqrt{2-x} \sqrt{x+2}$

15. amistre64

$y' = \frac{Dx}{\sqrt{1-\frac{x}{2}^2}} \rightarrow Dx = \frac{1}{2}$

16. anonymous

thats the derivative....forgot to close bracket lol

17. anonymous

I DID IT DIFF! :P

18. amistre64

I wanna change my vote :) y = x/2 ;) but I probably missed that one too

19. anonymous

lol! ha this is bad... i dont like this question!

20. amistre64

ack!! how can a fraction = 0 if its got a constant up top....

21. anonymous

yo this is messed...

22. anonymous

cuz the derivative of that equation will be the equation of the tangent slope...it cant be ny of those options :S...

23. amistre64

take this question, throw it in a sack, burn it in the fireplace, kill a chicken and spread its blood around the place to ward off any evil spirits that might rise from the ashes... ;)

24. amistre64

come to think of it, when does sin^-1 have a hump in it?

25. anonymous

lmao!!!

26. anonymous

I thank you guys for all of the help! I can't exactly figure it out myself. Tricky tricky. tisk tisk. :)