Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
Show that every point on the curve y=b sin (x/a), where the curve meets the axes of x, is a point of inflextion.
Do i have to plainly show that x=0 is a POI or its asking for something else?
 2 years ago
 2 years ago
Show that every point on the curve y=b sin (x/a), where the curve meets the axes of x, is a point of inflextion. Do i have to plainly show that x=0 is a POI or its asking for something else?
 2 years ago
 2 years ago

This Question is Closed

amistre64Best ResponseYou've already chosen the best response.1
inflection tends to be a found by a second derivative; and tested for cavage
 2 years ago

arcticf0xBest ResponseYou've already chosen the best response.0
yeah i know that, but the language isnt very clear up there.
 2 years ago

amistre64Best ResponseYou've already chosen the best response.1
looks like: b sin(x/a)/a^2 is the second derivative to me
 2 years ago

amistre64Best ResponseYou've already chosen the best response.1
since b=0 is trivial; it looks to be what x/a = any mutiple of pi
 2 years ago

arcticf0xBest ResponseYou've already chosen the best response.0
sorry didnt get that.
 2 years ago

amistre64Best ResponseYou've already chosen the best response.1
how to "show" it? i aint got a clue
 2 years ago

amistre64Best ResponseYou've already chosen the best response.1
sin(n*pi) = 0 so when x/a = n*pi we are at zero
 2 years ago

arcticf0xBest ResponseYou've already chosen the best response.0
yeah thats where i came, so is that the answer fianlly, x=0
 2 years ago

amistre64Best ResponseYou've already chosen the best response.1
x = a n*pi would seem to be the answer to me; but since n is an arbitrary integer then a*n would have to be an interger as well.
 2 years ago

amistre64Best ResponseYou've already chosen the best response.1
other than that; I got no idea what the "answer" might entail ....
 2 years ago

arcticf0xBest ResponseYou've already chosen the best response.0
umm, it says, where the curve meets the axes of x, so y=0 at that point, this only gives x=0.
 2 years ago

phiBest ResponseYou've already chosen the best response.0
inflection point is where the second derivative changes sign. we know that y=b sin (x/a) crosses the xaxis when x/a is some multiple of 2pi the 2nd derivative at these same points is b sin(x/a)/a^2 = 0 also, if we go a dx distance below x/a and a little distance dx above x/a, the 2nd derivative changes sign. So we are at an inflection point.
 2 years ago

arcticf0xBest ResponseYou've already chosen the best response.0
That seems clear, understood, thank you phi and amistre for your time :)
 2 years ago

phiBest ResponseYou've already chosen the best response.0
*crosses the xaxis when x/a is some multiple of pi
 2 years ago
See more questions >>>
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.