Hi, not sure what to do here. please help.

find the equations of the curves y=f(x+2) and y=f(x)+2, in terms of x, and use these equations to find the coordinates of the points where these curves cross the y-axis.

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- Dec 2nd 2006, 01:50 AMbecca999sketching curves-transformation curves f(x)!!!!
Hi, not sure what to do here. please help.

find the equations of the curves y=f(x+2) and y=f(x)+2, in terms of x, and use these equations to find the coordinates of the points where these curves cross the y-axis. - Dec 2nd 2006, 01:54 AMCaptainBlack
- Dec 2nd 2006, 05:11 AMbecca999
well it a says y=f(x) where f(x)=(x-1)(x+2) but then how do you work out the equations of the curves y=f(x+2) and y=f(x)+2 in therms of x and finding coordinates??

- Dec 2nd 2006, 06:55 AMCaptainBlack
If $\displaystyle f(x)=(x-1)(x+2)$, then

$\displaystyle

f(x+2)=((x+2)-1)((x+2)+2)=(x+1)(x+4)

$

so the equation of $\displaystyle y=f(x+2)$ is:

$\displaystyle y=(x+1)(x+4)$

similarly:

$\displaystyle y=f(x)+2=(x-1)(x+2)+2=x^2+x=x(x+1)$

so:

$\displaystyle y=x(x+1)$

RonL