# Thread: I need help with inflatation

1. ## I need help with 1st and 2nd deviation tests

I'm having a little trouble with my calculus problems. I need to find critical values, find x and y intercept, find if its increasing or decreasing and concade up or down.
Here are the problems i'm having trouble with. I don't even know know where to start. I'm having alot of trouble so any help will be appreicated.

Problems

1. -x^3+6x^2-9x+1

2. -x^3-12x^2-2

3. -x^2-8x-10

4. x^3-6x^2+9x+3

2. Originally Posted by BJenkins2009
I need to find critical values, find x and y intercept, find if its increasing or decreasing and concade up or down....I don't even know know where to start.
Ouch! They were supposed to have covered all of this before assigning homework on it, and some of this was supposed to have been covered back in algebra!

To learn how to find x- and y-intercepts, try here. Note that, to find the x-intercepts, you'll be needing to solve polynomials, so learn how to solve quadratics first, and then move on to the various techniques needed for solving polynomials.

"Critical points" are found using "derivatives", and the sign of the derivative (or else the use of the second derivative) helps you find the intervals of increase and decrease, which is related to the concept of slope.

To get to the point where you can answer this sort of exercise usually takes about a month in a differential calculus course, but you can try self-study through other texts or online, such as Paul's Online Math Notes or Karl's Calculus Tutor.

Good luck!