If you were integrating to find the area, then yes, make it positive. If, for example, the area is underneath the x-axis, integrating the function will give you a negative answer.
I prefer C4 to C3 in terms of the syllabus, but I just know that I'll end up making a minor cock up on a few parts as always. It's annoying because the maths isn't anywhere near as hard as some make out, but I always mess up in exam situations!
If you have to work out area or volume it has to be positive. Though if your not asked to work out area/ volume i guess you can just leave it as a negative.
Hi guys, i'm ready for this exam but theres one thing that always trips me. When solving differential equations, what side do you gather constants on? E.G dx/dt=15(5x-1) ...do you re-arrange to 1/15(5x-1) dx=dt
or 1/(5x-1) dx = 15dt
do the second because then you can bring dt over to the other side.