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GRE Math 2

Subjects : gre, math

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What is a '30:60:90' triangle?
Pi*r^2
2 pi r
This is an equilateral triangle that has been divided along its height. Interior angles are 30:60:90 degrees. Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse. This allows you to deduce any side - given
½(base x height) [or (base x height)÷2]

2. What'S a handy rough estimate for a circle'S perimeter - if you know it'S diameter?

3. What is the point-slope form?
Groups - teams - or committees.
x² -2xy + y²
(y-y1)=m(x-x1)
y = k/x

4. What is the factored version of x² + 2xy + y² ?
2lw+2lh+2wh
The set of points which are all the same distance (the radius) from a certain point (the center).
(x+y)²
The total # of possible outcomes.

5. How do you multiply powers with the same base?
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
Pir^2h
2(pi)r(r+h)
2(lw+wh+lh)

6. Rough est. of v3 =
(y2-y1)/(x2-x1)
This triangle is a square divided along its diagonal. Interior angles are 90:45:45 degrees. The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
2Length + 2width [or (length + width) x 2]
1.7

7. What is the average speed?
2x2x2x5x5
Total distance/total time
1/2bh
x°/360 times (?r²) - where x is the degrees in the angle

8. If something is possible but not certain - what is the numeric range of probability of it happening?
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
(n degrees/360) * 2(pi)r
Between 0 and 1.
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.

9. What'S the most important thing to remember about charts you'll see on the GRE?
x²-y²
1
That - unlike a normal chart - they are constructed to HIDE information or make it HARDER to understand. Be sure to scroll down - read everything - and look carefully for hidden information - asterisks - footnotes - small print - and funny units.
Bh

10. (a+b)(a-b)=
A²-b²
(n degrees/360) * 2(pi)r
2x2x2x5x5
1/3pir^2*h

11. Perimeter of a square
This is an equilateral triangle that has been divided along its height. Interior angles are 30:60:90 degrees. Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse. This allows you to deduce any side - given
4s (where s = length of a side)
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
Arrangements - orders - schedules - or lists.

12. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or B)
N x M
Probability A + Probability B
The four big angles are equal and the four small angles are equal
Probability A * Probability B

13. What is a 'Right isosceles' triangle?
(n degrees/360) * 2(pi)r
This triangle is a square divided along its diagonal. Interior angles are 90:45:45 degrees. The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
1
Less

14. Does order matter for a permutation? How about for a combination?
1. Given event A: A + notA = 1.
1/2bh
Order does matter for a permutation - but does not matter for a combination.
That - unlike a normal chart - they are constructed to HIDE information or make it HARDER to understand. Be sure to scroll down - read everything - and look carefully for hidden information - asterisks - footnotes - small print - and funny units.

15. What do combination problems usually ask for?
Multiply all elements of both sides of the equation by 2 (the denominator of the fraction). This will produce 10x + 3 = 14x. Solve from there: 3 = 4x - x = 3/4.
Groups - teams - or committees.
1/x^a
1/2bh

16. Chord
A segment connecting the center of a circle to any point on the circle
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
The distance from one point on the circle to another point on the circle.
Multiply all elements of both sides of the equation by 2 (the denominator of the fraction). This will produce 10x + 3 = 14x. Solve from there: 3 = 4x - x = 3/4.

17. List two odd behaviors of exponents
The range is the difference between the biggest and smallest numbers in the set. Example: for the set {2 -6 -13 -3 -15 -4 -9} the smallest number is 2 - largest is 15 - so the range is 15-2=13.
A=?r2
1. Raising a fraction (between 0 and 1) to a power greater than 1 results in a SMALLER number. For example: (1/2)² = 1/4.2. A number raised to the 0 power is 1 - no matter what the number is. For example: 1 -287° = 1.
y = mx + b -- where: x -y are the coordinates of any point on the line (allows you to locate) m is the slope of the line b is the intercept (where the line crosses the y-axis) - Sometimes on the GRE - 'a' is substituted for 'm' - as in 'y = ax + b'.

18. Sector
The part of a circle that looks like a piece of pie. A sector is bounded by 2 radii and an arc of the circle.
1/2bh
x² + 2xy + y²
1. Given event A: A + notA = 1.

19. What is the side ratio for a 30:60:90 triangle?
The equation must be set equal to zero. If during the test one appears that'S not - before you can solve it you must first manipulate it so it is equal to zero.
This is an equilateral triangle that has been divided along its height. Interior angles are 30:60:90 degrees. Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse. This allows you to deduce any side - given
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
2(pi)r

20. What is the unfactored version of x²-y² ?
x² + 2xy + y²
x°/360 times (?r²) - where x is the degrees in the angle
(x+y)(x-y)
1

21. For a bell curve - what three terms might be used to describe the number in the middle?
The average - mean - median - or mode.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
(a+b)²
½(base x height) [or (base x height)÷2]

22. x^a * x^b = x^__
1. Given event A: A + notA = 1.
Probability A * Probability B
A+b
C =?d

23. Surface Area of Sphere
1/1
4s (where s = length of a side)
4pir^2
The total # of possible outcomes.

24. Define the median of a set of numbers - and how to find it for an odd and even number of values in a set.

25. What is the area of a triangle?
Pir^2h
(x+y)(x-y)
1/2bh
y = kx

26. How do you find the nth term of an arithmetic sequence?
1/1
T1 + (n-1)d
Probability A * Probability B
The equation must be set equal to zero. If during the test one appears that'S not - before you can solve it you must first manipulate it so it is equal to zero.

27. What is 'absolute value' - and how is it represented?

28. What is the area of a cylinder?
The set of points which are all the same distance (the radius) from a certain point (the center).
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
2(pi)r(r+h)
Ac+ad+bc+bd

29. Area of Circle
(x-y)²
(n/2) * (t1+tn)
(pi)r^2
Pi*r^2

30. The length of one side of any triangle is ____ than the sum of the other two sides.
The part of a circle that looks like a piece of pie. A sector is bounded by 2 radii and an arc of the circle.
A median is the middle value of a set of numbers. For an odd number of values - it'S simply the middle number. For an even number of values - take the average of the center two values.
Less
Order does matter for a permutation - but does not matter for a combination.

31. Perimeter (circumference) of a circle
1/2bh
That - unlike a normal chart - they are constructed to HIDE information or make it HARDER to understand. Be sure to scroll down - read everything - and look carefully for hidden information - asterisks - footnotes - small print - and funny units.
An ange whose vertex is the center of the circle
2 pi r

32. What number goes on the bottom of a probability fraction?
The range is the difference between the biggest and smallest numbers in the set. Example: for the set {2 -6 -13 -3 -15 -4 -9} the smallest number is 2 - largest is 15 - so the range is 15-2=13.
The total # of possible outcomes.
(n degrees/360) * 2(pi)r
(n/2) * (t1+tn)

33. What is the area of a sector?
The four big angles are equal and the four small angles are equal
That they often have not just one answer - but two. For example - solving x² -10x + 24 = 0 factors to (x-4)(x-6)=0 - which means x could equal either 4 or 6. Just accept it.
(n degrees/360) * (pi)r^2
?d OR 2?r

34. Surface Area of Cylinder
2x2x2x5x5
Opens down
2pir^2 + 2pir*h
(x+y)(x-y)

35. Circumference of cirlce using diameter
Pi*d
(pi)r^2
S^2
Equal

36. Define 'proportionate' values
x²-y²
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
A=?r2
2Length + 2width [or (length + width) x 2]

37. Area of Trapezoid
?r²
(y-y1)=m(x-x1)
1/2 h (b1 + b2)
y = k/x

38. Area of a trapezoid
½(b1 +b2) x h [or (b1 +b2) x h÷2]
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
Total distance/total time
A digit is a number that makes up other numbers. There are ten digits: 0 -1 -2 -3 -4 -5 -6 -7 -8 -9. Every 'number' is made up of one or more digits. For example - the number 528 is made up of three digits - a 5 - a 2 - and an 8.

39. Define a factorial of a number - and how it is written.
The factorial of a number is that number times every positive whole number smaller than that number - down to 1. Example: 6! means the factorial of 6 - which = 65432*1 = 720.
(y-y1)=m(x-x1)
(x+y)(x-y)
b±[vb²-4ac]/2a

40. Area of a sector
y2-y1/x2-x1
x°/360 times (?r²) - where x is the degrees in the angle
½(b1 +b2) x h [or (b1 +b2) x h÷2]
2(pi)r(r+h)

41. How do you find the nth term of a geometric sequence?
2pi*r
Bh
An isoceles right angle. Remember that interior angles are 90:45:45 degrees. The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
T1 * r^(n-1)

42. Area of Triangle
1/3Bh
Equal
1/2bh
T1 * r^(n-1)/(r-1)

43. Central Angle
An ange whose vertex is the center of the circle
2x2x2x5x5
y = mx + b -- where: x -y are the coordinates of any point on the line (allows you to locate) m is the slope of the line b is the intercept (where the line crosses the y-axis) - Sometimes on the GRE - 'a' is substituted for 'm' - as in 'y = ax + b'.
Bh

44. Point-Slope form
y-y1=m(x-x1)
4s (where s = length of a side)
Zero is even. It is an integer. It is neither positive nor negative. Zero multiplied by any other number = zero. You cannot divide by zero.
Bh

45. How do you get rid of the fraction in this equation: 5x + 3/2 = 7x
(y-y1)=m(x-x1)
y-y1=m(x-x1)
This is an equilateral triangle that has been divided along its height. Interior angles are 30:60:90 degrees. Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse. This allows you to deduce any side - given
Multiply all elements of both sides of the equation by 2 (the denominator of the fraction). This will produce 10x + 3 = 14x. Solve from there: 3 = 4x - x = 3/4.

46. x^-a =
A digit is a number that makes up other numbers. There are ten digits: 0 -1 -2 -3 -4 -5 -6 -7 -8 -9. Every 'number' is made up of one or more digits. For example - the number 528 is made up of three digits - a 5 - a 2 - and an 8.
1/x^a
2(pi)r(r+h)
Bh

47. Quadratic Formula
Last term
b±[vb²-4ac]/2a
(y-y1)=m(x-x1)
?r²

48. Surface Area of rectangular prism
2l+2w
2 pi r
2lw+2lh+2wh
Calculate and add the areas of all of 6 its sides.Example: for a rectangle with dimensions 2 x 3 x 4 - there will be 2 sides each - for each combination of these dimensions. That is - 2 each of 2x3 - 2 each of 3x4 - and 2 each of 4x2.

49. Explain the special properties of zero.
1/2 h (b1 + b2)
4pir^2
Zero is even. It is an integer. It is neither positive nor negative. Zero multiplied by any other number = zero. You cannot divide by zero.
The length of any one side of a triangle must be less than the sum of the other two sides. It must also be greater than the difference between the other two sides. So - 'A' will always be < B+C - and > B-C or C-B.

50. Volume of prism
Bh
Multiply each numerator by the other fraction'S denominator. Example: 3/7 and 7/12. Multiply 312 = 36 - and 77 = 49. If you completed the full calculation - you'd also cross-multiply the denominators - but you don'T have to in order to compare values
A(b+c) = ab + ac a(b-c) = ab - ac For example - 12(66) + 12(24) is the same as 12(66+24) - or 12(90) = 1 -080.
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.