excel de resumo de estudo para teste de matemática do gre (2014)
DESCRIPTION
Excel que contém abas com resumos e dicas para o teste de matemático do GRE test (Graduate Record Examinations) da ETS.TRANSCRIPT
Termo/notação
Factor RemainderPrime numberComposite numberOnes/Units digitTens digitHundreds digitThousands digitTenths digitHundredths digitThousandths digit4 3/8 is 35/8-10 1/2 is -21/20!=10^0 is not definedf(g(x))Similar trianglesCongruent trianglesHypotenuseLegs of a triangleOpposite sides of a lineRight anglex-interseptCurly bracketDisjoint setsMean Value
MedianValue
Mode value
RangeInterquartile rangeQuartilePercentile
Outcome
(Population) Standard Deviation
Sample Standard Deviation
Mean of a random variable
FulcrumRevenueProfitQuartBoxplotScatter PlotYield1 mile = 5280 feet
RadiusIrrational numbersRatio of A to BPrime factorizationLike termsQuadratic equation(x^a)(x^b)=x^(a+b)(x^a)( y^a)=(xy)^a(x^a)^b=x^(ab)Fatorar expressões de segundo grau (ver métodos 1 e 2): http://pt.wikihow.com/Fatorar-Polin%C3%B4mios-de-Segundo-Grau-(Equa%C3%A7%C3%B5es-Quadr%C3%A1ticas)Simple interest rate
Compound interest rate
Compound interest rate
Simetria em relação ao y=x
The graph of h(x)+c is the graph of h(x) shifted upward by c units. The graph of h(x)−c is the graph of h(x) shifted downward by c units. The graph of h(x+c) is the graph of h(x) shifted to the left by c units. The graph of h(x−c) is the graph of h(x) shifted to the right by c units.Fatores notáveis
Mean of a random variable
Mean and median of a continuous random variable
Vírgula é ponto e ponto é vírgula (português para inglês)
Significado
Fator (número inteiro pelo qual um outro número inteiro é divisível)Resto de uma divisão. É sempre positivoNúmero primo (maior que um)Número maior que um que não é primoDígito da unidadeDígito da dezenaDígito da centenaDígito do milhar0.X0.0X0.00X4*(8/8) + 3/8-(10*(2/2)+1/2)Zero fatorial é igual a 1
Composition of f with gTwo triangles that have the same shape but not necessarily the same sizeTwo triangles that have the same shape and sizeHipotenusaCatetosDe um lado da linha e do outro lado da linhaÂngulo retoThe insersection of a graph at the x-axis in a coordinate system{}If A and B have no elements in common, they are called disjoint sets or mutually exclusive sets.
The median of an odd number of data is the middle number when the data arelisted in increasing order; the median of an even number of data is the arithmeticmean of the two middle numbers when the data are listed in increasing order.
Diferença entre o maior e menor número da listathird quartile minus the first quartile (o que está entre o primeiro e terceiro quartis?)3 números que dividem uma lista em 4 partes iguais (baseado em medianas)99 números que dividem uma lista em 100 partes iguais (baseado em medianas)
For a list of data, where the arithmetic mean is denoted by m, the standarddeviation of the data refers to the nonnegative square root of the mean of thesquared differences between m and each of the data. This statistic is also knownas the population standard deviation and is not to be confused with the samplestandard deviation.
The same of the population standard deviation, but, as opposed to dividing by (n), divide by (n-1)Result
Value that occurs more often (if there isn't repeated values, then there is no mode value. Also, there may be more than one mode)
The mean of the random variable X is the sum of the products XP(X) for all values of X. It's also called the expected valueor the mean of the probability distribution.
The mean of a continuous random variable X is the point m on the x-axis at whichregion under the distribution curve would perfectly balance if a fulcrum wereplaced at x=m. The median of X is the point M on the x-axis at which the linex=M divides the region under the distribution curve into two regions of equalarea.Fulcro, eixoReceitaRevenue minus costMedida de volume: Aproximadamente 946,35mlDiagrama de Caixa (usa teoria da divisão por quartis)Gráfico de dispersãoResulta
Raio de um círculoNumber that do not terminate neither repeat.A/BFactors of a number that are only composed by prime numbersTerms in na equation that have the same variablesVariables are to a maximum power of two
Fatorar expressões de segundo grau (ver métodos 1 e 2): http://pt.wikihow.com/Fatorar-Polin%C3%B4mios-de-Segundo-Grau-(Equa%C3%A7%C3%B5es-Quadr%C3%A1ticas)
V=P(1+r/100)^t
Trocar o x por y e o y por x na equação. The graph of h(x)+c is the graph of h(x) shifted upward by c units. The graph of h(x)−c is the graph of h(x) shifted downward by c units. The graph of h(x+c) is the graph of h(x) shifted to the left by c units. The graph of h(x−c) is the graph of h(x) shifted to the right by c units.
(a+b)² = a² + 2ab + b²; (a-b)² = a² - 2ab + b²; a² - b² = (a+b)(a-b)
The mean of the random variable X is the sum of the products XP(X) for all values of X. It's also called the expected valueor the mean of the probability distribution.
IMPORTANTE! VOCÊ JÁ CONFUNDIU ISSO E ERROU. ERA QUESTÃO DE ENTRADA NUMÉRICA, AÍ NÃO TEM NEM ITEM PRA CONFERIR A ORDEM DE GRANDEZA!
V=P(1+rt/100); sendo r o juros em percentagem
V=P(1+r/(100*n))^(n*t); sendo r o juros em um período e n o número de vezes neste período que o juros é contabilizado. As the compounding period decreases (when "n" is bigger), the final ammount of money is greater!
Exemplo
the integer 4 has six factors: −4, −2, −1, 1, 2, and 4-17/4 resulta -3 com resto +42,3,5,7,11, etc2,4,6,7,9,10, etc
585=(3^2)*(5)*(13)In w3z+5z2−z2+6; the terms 5z2 and −z2 are like terms
Fatorar expressões de segundo grau (ver métodos 1 e 2): http://pt.wikihow.com/Fatorar-Polin%C3%B4mios-de-Segundo-Grau-(Equa%C3%A7%C3%B5es-Quadr%C3%A1ticas)
Se é dado o juros anual "r", para saber o mensal, utilizamos n=12, ou seja, dividimos os juros por 12, e contabilizamos a cada mês (por isso multiplicada o expoente por 12).
y=x^2 e y=raiz(x) são simétricas em relação a x=y, assim y=raiz(x) é uma parábola na origem com a abertura para o lado direito.
O que pode ser assumido e o que não pode? Por exemplo, se não especificado, medidas de distâncias e ângulos não podem ser assumidos maiores ou menores que outros, mesmo que pareçam ser.
Termo/notação
Geometry
Regular polygon
Área trapézio
Área paralelogramo = b*h
Área triângulo equilátero
Área triângulo qualquerAltitude
Propriedade de triângulos
Propriedade de triângulos
If a polygon has n sides, it can be divided into n−2 triangles
the sum of the measures of the interior angles of an n-sided polygon is (n−2)(180 )
A polygon is inscribed in a circle if all its vertices lie on the circle, or equivalently,the circle is circumscribed about the polygon
Propriedade de triângulos (cai bastante - figuras ficam fora de escala, tem que imaginar bem ou desenhar)
Circle Properties
Speacial Right triangles
Similar triangles
Rhombus
Área de losango (2 formas)
Convex polygonRegular polygonPythagorean triples
Diagonais de losangos formam ângulo reto
Significado
All the internal angles are equal
A=(1/2)*(b1+b2)*hParalelogramo: quadrilátero cujos lados opostos são paralelos.
A=(raiz(3)*L^2)/4
height of triangleRAÍZ(p*(p-a)*(p-b)*(p.c)) em que p=(a+b+c)/2
Losango
All interior angles less than 180ºequal sides and equal angles3-4-5; 5-12-13; 8-15-17; 7-24-25
O que pode ser assumido e o que não pode? Por exemplo, se não especificado, medidas de distâncias e ângulos não podem ser assumidos maiores ou menores que outros, mesmo que pareçam ser.
Significado
The x point when y=0The y point when x=0
slope=(y2-y1)/(x2-x1); b=y_intercept ; Find "b" inserting one point (pair x,y) into the general equation
Termo/notação
Mean, median and mode
Weighed Averages
Normal Distribution
Properties when mean=mediam
Range and
Standard Deviation
On the GRE QC's, always warm up your imagination and have an eye out for ---"could I answer this without doing a full calculation?". So.... Pay attention to the things explained in the videos that may seem obvious, but you usually don't use to solve questions! (for example, the "example" part of the line about "weighed averages in this plan"
Excluding Q2 from the lesser and greater numbers is particularly important when the list has an odd number of terms.
http://magoosh.com/gre/2012/how-to-do-gre-math-faster/
B is not necessarily true, because the last term of the lesser number and the first term of the greater numbers can be equal to each other and the median. (remembering that the list has an even number of terms)
Termo/notaçãoReciprocal of number X
Word problems
Comparação de frações ao adicionar números no numerador e no denominador
Comparando frações. Maior ou menor?
Termo/notaçãox^n2^5
Units Digit Question
Equations with exponents
Working with formulas
Leaving the denominator with no roots
Significadox=base ; n=exponent"Two root Five"
When there would be a complex calculation, maybe it's simpler to plug in a value in the formula (useful in comparison questions), e.g. value "1"
Na potenciação de equações com raízes, deve-se verificar as respostas para ver se são válidas quando estiver elevando a potências pares (2,4,6,8, etc)
Termo/notação
Listing
Counting Strategy 1
Fundamental Counting Principle
Counting Strategy 2: Restrictions
Arrangement when there are alike objects
Combination
Counting Strategies II
Important property!
When to use combinations and when to use the fundamental counting principles or other methods?
Simplification of thecombinatorial formula
Significado
Listing the possible answer may be a good strategy when you have no insight about the problem.
Strategy 1: Directly adhere to the restrictions;Strategy 2: Use the restriction rule showed in the figure of the example.
Exemplo
If the problem allows repetition, that is like the example above (2*2*2=8). If there cannot be repetitions, it may be a permutation (e.g.: 3! = 3*2*1) (arrangement) (<-- Afirmação errada?)
Termo/notação
First rule
Mutually exclusive (disjoint)
Independent events
Generalized AND Rule
Binomial
Approximate rules (often, but not always)
Simple OR Rule andGeneralized OR Rule
With and without replacement
AND rule for independent events
Which technique to use?
The "At least scenario" (or "at most")
Guessing Strategy 1 - Instincts of real world life
Guessing Strategy 2 - Complement Rule = possible complement options
Guessing Strategy 3 - Knowing the possible range of responses.
Significado
When one event has no bearing or influence on the other events
For independent events:
Two events are mutually exclusive when they can't occur at the same time --> P(A and B)=0
where: P(A|B) = Probability of A, given condition B.
Significado
Check the answers first to see if you need to do calculations or extensive calculations, or you can just estimate na approximate answer
Termo/notação
Inequalities I
Inequalities II
Modules (absolute values)
Rational Expressions
Simplifying complex fractions
Testing Cases
Factoring Rational Expressions
Significado
In the example on the right: You can simplify the rational expressions of the second term, but you need to write a restriction: x is different of 4 (otherwise you would be permitting a division by zero --> indefinite)
Termo/notação
Motion QuestionsShrinking and Expanding Gaps
Rates and work problems(similar treatment of any velocity problem)
Termo/notação
Prime numbers facts
Factors of prime numbers
Testing prime numbers less than 100
Testing if any number is prime
Finding the number of factors of N
Odd and Even numbers
Odd and Even numbers
Divisibility Rules
Odd and Even numbers(see note 1)Another note: Zero is not positive neither negative
Pay attention to the question and DO NOT make deliberate assumptions!
Great Common FactororGreat Common Divisor
Least Common Multiple=Least Common Denominator (for simplifying equations)
Significado
A regra acima na verdade é a seguinte:1° passo: Tirar a raiz do número em questão √241 = 15,524...
2° passo: Aproxime o resultado para cima 15,524... => 16
3° passo: Ache todos os números primos menores que o resultado dado. Os primos menores que 16 são 2, 3, 5, 7, 11 e 13
4° passo: Veja se algum desses primos dividem o número inicial. Nenhum dos primos obtidos(2, 3, 5, 7, 11 e 13) dividem 241. Portanto, 241 é primo!
1) Put the numbers in prime factors2) Find the common factors and multiply them.
1) Find the Great Common Factor2) Multiply the two numbers and then divide by the Great Common Factor
By 2: Even numbersBy 3: Sum of all digits must be divisible by 3By 4: The last two digits must be divisible by 4By 5: Units digit must be "0" or "5"By 6: Must be divisible by 2 and 3By 9: Sum of all digits must be divisible by 9
In the example at the left, we do not know if Q or R are integers. They may be fractions. Then, one of then could be even too, or both could be fractions.
A=24; B=32
1) A=2^3 * 3 B=2^52) GCF=2^3 = 8
A=24; B=32
1) GCF= 82) LCM=24*32/8 = 96
Termo/notação
Factor 134Remainder 134Prime number 134Composite number 134Ones/Units digitTens digitHundreds digitThousands digitTenths digitHundredths digitThousandths digit4 3/8 is 35/8-10 1/2 is -21/20!=10^0 is not definedf(g(x))Similar trianglesCongruent trianglesHypotenuseLegs of a triangleOpposite sides of a line 137Right anglex-intersept 138Curly bracket
Disjoint sets138
Mean Value 139
MedianValue
139
Mode value
Range
Interquartile range
QuartilePercentile
Página do ETS guide
(Population) Standard Deviation
Outcome
140
FulcrumRevenue 142Profit 142QuartBoxplot 107Scatter Plot 107Yield1 mile = 5280 feet
RadiusIrrational numbers 214Ratio of A to B 215Prime factorization 210Like terms 222Quadratic equation 223(x^a)(x^b)=x^(a+b)(x^a)( y^a)=(xy)^a(x^a)^b=x^(ab)Fatorar expressões de segundo grau (ver métodos 1 e 2): http://pt.wikihow.com/Fatorar-Polin%C3%B4mios-de-Segundo-Grau-(Equa%C3%A7%C3%B5es-Quadr%C3%A1ticas)Simple interest rate
Compound interest rate
Compound interest rate
(Population) Standard Deviation
Sample Standard Deviation
Mean of a random variable
Mean and median of a continuous random variable
Vírgula é ponto e ponto é vírgula (português para inglês)
Simetria em relação ao y=x
The graph of h(x)+c is the graph of h(x) shifted upward by c units. The graph of h(x)−c is the graph of h(x) shifted downward by c units. The graph of h(x+c) is the graph of h(x) shifted to the left by c units. The graph of h(x−c) is the graph of h(x) shifted to the right by c units.Fatores notáveis
GeometryIf a polygon has n sides, it can be divided into n−2 trianglesthe sum of the measures of the interior angles of an n-sided polygon is (n−2)(180 )Regular polygon
Área trapézio = (1/2)*(b1+b2)*hÁrea paralelogramo = b*h
Área triângulo equiláteroÁrea triângulo qualquerAltitude
Propriedade de triângulos
Propriedade de triângulos
A polygon is inscribed in a circle if all its vertices lie on the circle, or equivalently,the circle is circumscribed about the polygon
Propriedade de triângulos (cai bastante - figuras ficam fora de escala, tem que imaginar bem ou desenhar)
Significado
Fator (número inteiro pelo qual um outro número inteiro é divisível)Resto de uma divisão. É sempre positivoNúmero primo (maior que um)Número maior que um que não é primoDígito da unidadeDígito da dezenaDígito da centenaDígito do milhar0.X0.0X0.00X4*(8/8) + 3/8-(10*(2/2)+1/2)Zero fatorial é igual a 1
Composition of f with gTwo triangles that have the same shape but not necessarily the same sizeTwo triangles that have the same shape and sizeHipotenusaCatetosDe um lado da linha e do outro lado da linhaÂngulo retoThe insersection of a graph at the x-axis in a coordinate system{}
The median of an odd number of data is the middle number when the data are
listed in increasing order; the median of an even number of data is the arithmeticmean of the two middle numbers when the data are listed in increasing order.
Diferença entre o maior e menor número da lista
third quartile minus the first quartile (o que está entre o primeiro e terceiro quartis?)3 números que dividem uma lista em 4 partes iguais (baseado em medianas)99 números que dividem uma lista em 100 partes iguais (baseado em medianas)
For a list of data, where the arithmetic mean is denoted by m, the standarddeviation of the data refers to the nonnegative square root of the mean of the
squared differences between m and each of the data. This statistic is also known
If A and B have no elements in common, they are called disjoint sets or mutually exclusive sets.
Value that occurs more often (if there isn't repeated values, then there is no mode value. Also, there may be more than one mode)
as the population standard deviation and is not to be confused with the samplestandard deviation.
Result
The mean of a continuous random variable X is the point m on the x-axis at whichregion under the distribution curve would perfectly balance if a fulcrum wereplaced at x=m. The median of X is the point M on the x-axis at which the linex=M divides the region under the distribution curve into two regions of equalarea.Fulcro, eixoReceitaRevenue minus costMedida de volume: Aproximadamente 946,35mlDiagrama de Caixa (usa teoria da divisão por quartis)Gráfico de dispersãoResulta
Raio de um círculoNumber that do not terminate neither repeat.A/BFactors of a number that are only composed by prime numbersTerms in na equation that have the same variablesVariables are to a maximum power of two
Fatorar expressões de segundo grau (ver métodos 1 e 2): http://pt.wikihow.com/Fatorar-Polin%C3%B4mios-de-Segundo-Grau-(Equa%C3%A7%C3%B5es-Quadr%C3%A1ticas)
V=P(1+r/100)^t
The same of the population standard deviation, but, as opposed to dividing by (n), divide by (n-1)
The mean of the random variable X is the sum of the products XP(X) for all values of X. It's also called the expected valueor the mean of the probability distribution.
IMPORTANTE! VOCÊ JÁ CONFUNDIU ISSO E ERROU. ERA QUESTÃO DE ENTRADA NUMÉRICA, AÍ NÃO TEM NEM ITEM PRA CONFERIR A ORDEM DE GRANDEZA!
V=P(1+rt/100); sendo r o juros em percentagem
V=P(1+r/(100*n))^(n*t); sendo r o juros em um período e n o número de vezes neste período que o juros é contabilizado
Trocar o x por y e o y por x na equação. The graph of h(x)+c is the graph of h(x) shifted upward by c units. The graph of h(x)−c is the graph of h(x) shifted downward by c units. The graph of h(x+c) is the graph of h(x) shifted to the left by c units. The graph of h(x−c) is the graph of h(x) shifted to the right by c units.
(a+b)² = a² + 2ab + b²; (a-b)² = a² - 2ab + b²; a² - b² = (a+b)(a-b)
If a polygon has n sides, it can be divided into n−2 trianglesthe sum of the measures of the interior angles of an n-sided polygon is (n−2)(180 )
All the internal angles are equal
Paralelogramo: quadrilátero cujos lados opostos são paralelos.
A=(raiz(3)*L^2)/4
height of triangleRAÍZ(p*(p-a)*(p-b)*(p.c)) em que p=(a+b+c)/2
Exemplo
the integer 4 has six factors: −4, −2, −1, 1, 2, and 4-17/4 resulta -3 com resto +42,3,5,7,11, etc2,4,6,7,9,10, etc
585=(3^2)*(5)*(13)In w3z+5z2−z2+6; the terms 5z2 and −z2 are like terms
Fatorar expressões de segundo grau (ver métodos 1 e 2): http://pt.wikihow.com/Fatorar-Polin%C3%B4mios-de-Segundo-Grau-(Equa%C3%A7%C3%B5es-Quadr%C3%A1ticas)
Se é dado o juros anual "r", para saber o mensal, utilizamos n=12, ou seja, dividimos os juros por 12, e contabilizamos a cada mês (por isso multiplicada o expoente por 12)
y=x^2 e y=raiz(x) são simétricas em relação a x=y, assim y=raiz(x) é uma parábola na origem com a abertura para o lado direito.