linearizing a function
approzimating the function for values of x close to c using the linear function
local linearity
if f is differentiable at x = c, then the linear function l(x) containing (c, f(c )) w/ slope f’(c ) is a close approximation to the graph of f for values of x close to c
dx =
change in x
dy
f’(x)dx
l(x)
f(c ) + f’(c ) (x-c)
indefinite integral
g(x) = ∫f(x)dx if and only if g’(x) = f(x)
K * f(x)dx =
K∫f(x)dx
(f(x) ± g(x))dx =
∫f(x)dx ± ∫g(x)dx + c
xn dx =
1/n+1 * xn+1 + C
exdx
ex + C
bxdx =
bx * l/ln(b)
u-substitution
the reverse chain rule for integration, where u = a function/something inside a composition
riemann sum
Rn = ∑ f(ck)∆xk
definite integral notation
∫ba f(x) dx
the mean value theorem
f is differentiable for all values of x in the open interval (a,b) and..
f is continuous for all values of x in the closed interval [a,b]
then there is at least 1 number x=c in (a.b) such that
f’(c) = (f(b)-f(a))/b-a
rolles theorem
if
f is differentiable for all values of x in the open interval (a,b) and..
f is continuous for all values of x in the closed interval [a,b] and..
f(a) = f(b) = 0
then there is at least 1 number x=c in (a,b) such that f’(c) = 0
the fundamental theorem of calculus
if f is an integrable function and if g(x) = ∫f(x)dx then ∫ba f(x)dx = g(b) - g(a)
∫ba (f(x) ± g(x))dx =
∫ba f(x)dx ± ∫ba g(x)dx
∫ba K * f(x)dx =
K ∫ba f(x)dx
∫ba f(x)dx if a<c<b =
∫ca f(x)dx + ∫bcf(x)dx
∫ab f(x)dx =
-∫ba f(x)dx
area of a region between two curves
∫ba (f(x)-g(x)) dx
average value of a function
= 1/b-a ∫ba f(x)dx
volume of a solid by plane slicing
V = ∫ba A(x)dx
the disc method
V = ∫ba π f(x)2dx
washer method
V = ∫ba π(f(x)2 - g(x)2)