Sunday, May 2, 2010

Post #37?

Well I was actually just studying..so I'm going to go over some random things.

Area formula: aSb top - bottom
Volume formula: (pi) aSb (top)^2 - (bottom)^2
QUESTION: when do you use aSb (top-bottom)^2?

limit rules as x--> infinity are really simple:
top degree = bottom degree-->divide coeffient
top degree < bottom degree-->0
top degree > bottom degree-->infinity

remember:

increasing/decreasing, max/min is FIRST derivative test
concave up/down, pt of inflection is SECOND derivative test

if original graph is postive then the deivative graph is increasing
if original graph is negative then the deivative graph is decreasing
QUESTION: how do you know if it is concave up/down?

for a piecewise the derivatives must equal in order for it to be differentiable

something I just learned:

d/dx (integral from 0 to x^2 (sin(t^3) dt)
= x^2[sinx^6]
*pull the top bound out to the front and plug in t^3 for x

tangent lines:
take derivative
set = to 0
solve for x
plug into point slope formula
*linearzation is much like tangent lines

average value:
1/b-a (aSb) equation

Mean Value Theorem:
plug in points to original equation
take those points you just found and the point given in problem to find slope
take derivative of orginial equation and set = to the slope

Position, Velocity, Acceleration:
P--> Postion
V--> Velocity
A--> Acceleration
*Going down take derivative; going up take integral

Calculator:
change direction-zeros on graph
bounds for integral-intersection on graph
graph stuff!

and:
a corner IS continuous but NOT differentiable
don't forget +C

I'm still worried about substitution & ln integration!

1 comment:

  1. The most common ln integration we see is when the derivative of the bottom is the top. When this happens, the integral is just ln of the absolute value of the bottom + c.
    Example:
    Integrate 2x/x^2 +6
    The derivative of the bottom is 2x, which is what is on the top
    so the integral of this is : ln |x^2+6| + c

    Example 2:
    Integrate cos(x)/sin(x)
    The derivative of sin (x) is cos(x).
    So the integral is: ln |sin(x)| + c

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