• December 5th 2012, 01:29 AM
Danthemaths
Hey guys,
I am a bit stuck answering this question. The question being:
If dy/dx = (x+3)(x-2), Find y

I expanded the brackets first of all but a bit stuck from here. Can anyone give me some guidance on what to do next?

Thanks
Danthemaths
• December 5th 2012, 02:00 AM
MarkFL
After expanding, you next want to integrate both sides with respect to x.
• December 5th 2012, 09:53 AM
Danthemaths
do we get two answers? because x=-3 and another x=2

thats the part i was stuck on, it there two answers to this question??
coz once the brackets are expanded you get dy/dx=x^2-x-1
integrate that you get: y=x^3/3-1
then dont you sub each x in? so y= (-3)^3/3-1 and then sub the other in to get y=(2)^3/3-1

and you get 2 y answers?

is this how you do this?
• December 6th 2012, 08:18 AM
sjmiller
If $\frac{dy}{dx}= (x+3)(x-2)$, then $y= \int (x+3)(x- 2)dx$. Once you have multiplied (x+3)(x-2) that will be an easy integral.