Question

y=x^3 has a point of inflection at x=o.
I know it is true but how i prove it with an statement?

Answer 1

You test the point by, take the Second Derivato on it.. and then you can test it by using, a point before 0 and after.. For exempel test with the point -1 and 1

Answer 2

you get a parabola

Answer 3

and the parabola touches the origin..is this fine?

Answer 4

@nabaz thankyou. it means i have to solve it.

Answer 5

No problem, is it a parabola...???

Answer 6

yeah , of course, u need proof?

Answer 7

i thouht it was a Curve ..

Answer 8

@thinker thankyou

Answer 9

if so, u have the answer wid u...just try substituting x=-1,1,0,-2,2,...... and you'll get corresponding y values, with which u can get a curve...and that curve is a parabola

Answer 10

now , is this fine?? @nabaz & @abhinn

Answer 11

yeah, i last thing... u mean this is a parabola.. http://en.wikipedia.org/wiki/File:X_cubed_plot.svg

Answer 12

Copie the text.. could get the hole adress..

Answer 13

no no....not that one...:).try this
http://en.wikipedia.org/wiki/File:Parabola.svg

this is a parabola...both of go to this link n see

Answer 14

*both of u

Answer 15

its like a "U" shape

Answer 16

Yes but this was a Y = x^3 and its not a parabole

Answer 17

Yes, but x3 is like a S with is lying downwards.

Answer 18

yeah...y=x^3 is a symmetric curve, but parabola looks like a "U" ...

Answer 19

haha.. my bad, i thought u meant that x^3 was a parabola

Answer 20

its ok:) nabaz

Answer 21

i wud like to give u both a hint

Answer 22

u der?

Answer 23

hint for what?

Answer 24

to know if an equation is parabola or what..only if u need it:)

Answer 25

yes, i know i think. ever x^2 x^4 x^6 .. ( not odd nrs )

Answer 26

exactly :)...good