notes for math Flashcards

1
Q

|x|=a, then x=

A

a or -a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

|x|<a></a>

A

-a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

|x|>a, then

A

x>a or x

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

when a linear inequality is expressed in slope intercept form and the inequality is < or <= then the region is… th opposite is true

A

below the line

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

a number or expression under a radical is referred to as a

A

radicand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

if the denominator is a binomial, use the … of the denominator to rationalize

A

conjugate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

the exterior angle of a triangle will be equal to the

A

sum of the other two (non-adjacent) angles of the triangle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

the perpendicular bisector of a chord passes through the

A

center of a circle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

congruent chords have congruent .. and vice versa

A

arcs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

arcs between parallel chords are

A

congruent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

arc length in radians:

A

s=theta*r

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

arc length in degrees

A

s= theta/180 pir

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

area of a sector in radians

A

A=1/2rs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

area of a sector in degrees

A

A=theta/360 pir^2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

sinx= (in terms of cos)

A

cos(90° -x)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

cosx= (in terms of sin)

A

sin(90°-x)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

number of elements in a group=

A

total number of elements x proportion of elements in a group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

confidence intervals describe the …. of the sampling method in terms of an interval

A

accuracy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

the smaller the confidence interval at a given confidence level, the more

A

accurate the sampling method

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

confidence interval=

A

sample statistic +- margin of error

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

margins of error reflect the confidence level: the higher the confidence level, the

A

smaller the margin of error

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

the greater the standard deviation, the greater the

A

margin of error

23
Q

if event a and b are mutually exclussive (the fulfillment of one event excludes the possibility of the other), then the probability is

A

P(A or B)= P(A) + P(B)

24
Q

for any two independent events a and b, the prob is

A

P(A and B)= P(A) * P(B)

25
dependent event prob
P(A and B)= P(A) * P(B|A)
26
amount of work completed=
rate of work * time word
27
worker A completes ... of the ob per hour and worker B completes .... of the job per hour; total time to complete =
1/x; 1/y; 1/ (1/x + 1/y)
28
percent change=
amount of change/original amount * 100%
29
concentration of A=
amount of substance A/ amount of substance B
30
to get the decimal/percent of a multiple of 1/10, 1/5, 1/4, 1/3, 1/2, or 3/4, take the fraction with the corresponding denominator, convert to a decimal, and
multiply by the numerator of the desired fraction get its decimal equivalent
31
area of a parallelogram:
A=bh
32
if you have two racios, a:b and b:c, you can derive a:c by finding a
common multiple of the b terms
33
linear model: y=
kx +x0
34
exponential equation:
y= a(1 + r)^x
35
when you have a group of evenly spaced terms, the mean and median will be
identical
36
you can find the mean of a group of evenly spaced terms by taking the
mean of the highest and lowest terms
37
... total cards in a deck
52
38
(ab)^c =
a^c * b^c
39
alternate interior angles and alternate exterior angles are
equal
40
ratio of 45-45-90 is
x:x:xroot2
41
ratio of 30-60-90 is
x: xroot3: 2x
42
right square pyramid volume
1/3 * l * w * h
43
right cone volume
1/3 (pi*r^2)*h
44
sphere volume
4/3 * pi * r^3
45
i^2
-1
46
i^3
-i
47
i^4
1
48
sin^2x + cos^2x=
1
49
pythagorean triplets:
7-24-25; 5-12-13; 3-4-5
50
correlations do not prove
causation
51
questions about breaking even involve
systems of equations
52
when comparing two data sets for consistency, consider both the
data center (mean/median)P and the spread(standard deviation/range)
53
the inverse of raising a quantity to the 5/2 power is raising t to the
2/5 power