MATH TIDBITS FOR GRE ONE

  1. THE SQUARE OF A NUMBER (XX) IS ALWAYS....
    GREATER THAN OR EQUAL TO ZERO.
  2. ANY EQUATION OR FUNCTION THAT IS LINEAR WILL ONLY HAVE X ____ ____ ___ ____ ____.
    • RAISED TO THE FIRST POWER. 
    • EX: f(x) = 2x - 7 

    Image Upload 2

    NO ABSOLUTES, NO EXPONENTS, ONLY TO THE FIRST POWER.
  3. WHAT DOES A QUADRATIC AND ABSOLUTE POWER GRAPHS LOOKS LIKE?
    NON LINEAR! Image Upload 4
  4. WHAT DOES A CUBIC AND SQUARE ROOT FUNCTION LOOK LIKE ON A GRAPH?
    NON LINEAR !Image Upload 6
  5. HOW DO YOU WORK WITH A NEGATIVE EXPONENT?

    EX: 2-4
    RECIPROCATE!

    2-4 = 1/2= 1/16 = .0625

    OR IF YOUR WORKING WITH IT IN A DIVISION PROBLEM USE THE FRACTION. 

    • EX:-20/ 2-4
    • =-20/1 * 1/ 2
    • = -20/ 16
    • =-1.25
  6. 43 donate 81.00
    21 donate 75.00
    16 donate 100.00

    QUESTION: WHAT IS THE AVERAGE DONATION PER PERSON?
    • (43*81) + (21*75) + (16*100)
    • ------------------------------------
    • 43 + 21 + 16 

    THE TAKE HOME HERE IS THAT THE QUESTION ASKED FOR THE AVERAGE PER PERSON. NOTICE HOW YOU ADDED ALL IN THE DENOMINATOR. 

    IF YOU JUST DIVIDED BY 3 THAT WOULD GIVE YOU THE AVERAGE OF THE DONATIONS, NOT THE PER PERSON'S DONATION.
  7. -10AND (-10)2

    WHAT IS THE DIFFERENCE AND HOW DO YOU KNOW?
    -102 = -(10 * 10) = -100

    (-10)2 = (-10) * (-10) = 100

    THINK OF IT THIS WAY: THE EXPONENT IS GOING GOING TO EFFECT WHAT IS ONLY NEXT TO IT. THE () HOLD EVERYTHING.

    WITH THEM YOU CAN ONLY WORK WITH THE NUMBER AND NOT THE SIGN IN FRONT OF IT.
  8. 55 % IS FEMALE BUY PRODUCT X. WHAT IS THE RATIO OF FEMALE TO MALE WHO BUY PRODUCT X?


    A.

    55 FEMALE MEANS 45 MALE. 

    NOW DIVIDE TO FIND RATIO.

    55/5 = 11  AND 45/5 = 9 

    • YOUR RATIO IS 11:9. 
    • MUST DIVIDE EVENLY.
  9. AREA OF A RECTANGLE FORMULA.
    Area = w × h

    Example: A rectangle is 6 m wide and 3 m high, what is its Area?Area = 6 m × 3 m = 18 m2
  10. PREIMETER OF A RECTANGLE FORMULA
    Perimeter = 2(w+h)

    Example: A rectangle has a width of 12 cm, and a height of 5 cm, what is its Perimeter?

    • Perimeter
    • = 2 × (12 cm + 5 cm)
    • = 2 × 17 cm
    • = 34 cm
  11. HOW DO YOU READ THIS?
    WHERE WOULD IT BE ON A GRAPH?
    f(f(-1))
    THINK OF IT THIS WAS. F=Y AND IT WILL TELL YOU THIS VIA THE X, WHICH IS IN THE ().

    THE -1 IS ON THE X AXIS.

    • FOLLOW THIS UP TO THE POINT ON THE Y AXIS. f(f(-1)). 
    • THIS GIVES YOU f(2). 

    DO THE SAME THING WITH f(2). GOTO 2 ON THE X AXIS AND FOLLOW IT UP TO THE Y COORDINATE, HERE IS 1. 

    Image Upload 8
  12. d - 3n
    7n - d =1

    WHAT IS D IN TERMS OF N?
    • THE WHOLE EQUATION IS = 1.
    • SO THE NUMERATOR & DENOMINATOR ARE EQUAL. 

    SET NUM=DOM AND SOLVE FOR N. BECAUSE THAT IS WHAT THE QUESTION ASKS FOR "IN TERMS OF".

    ANS IS D= 5N. OR "5 TIMES N".

    Image Upload 10
  13. Image Upload 12













    Quantity A Quantity B
    x y


    (A) Quantity A is greater.
    (B) Quantity B is greater.
    (C) The two quantities are equal.
    (D) The relationship cannot be determined from the information given.
    If Image Upload 14 then Image Upload 16 so in this case, Image Upload 18 but if Image Upload 20 then Image Upload 22 so in that case, Image Upload 24 

    Thus, the correct answer is Choice D,the relationship cannot be determined from the information given.














  14. Image Upload 26
    Quantity A Quantity B
    Image Upload 28 y





    (B)

    Y IS SMALLER BECAUSE IT IS BEING DIVIDED IN A.











  15. Quantity A Quantity B
    Image Upload 30 Image Upload 32



    (A) Quantity A is greater.
    (B) Quantity B is greater.
    (C) The two quantities are equal.
    (D) The relationship cannot be determined from the information given.
    • Set up the initial comparison:
    • Image Upload 34
    • Then simplify:
    • Step 1: Multiply both sides by 2 to get  Image Upload 36
    • Step 2: Add Image Upload 38 to both sides to get  Image Upload 40
    • Step 3: Simplify the right-hand side using the fact that Image Upload 42 to get  Image Upload 44
    • The resulting relationship is equal to (=). In reverse order, each simplification step impliesequal to in the preceding comparison. So Quantities A and B are also equal. Thus, the correct answer is Choice Cthe two quantities are equal.
  16. Image Upload 46
    Image Upload 48
  17. ADD THIS TOGETHER:

    Image Upload 50
    Image Upload 52
  18. (-3)2 AND -32
    (-3)2 = (-3)(-3) = 9 

     -32  = -(3 *3) = -9

    Note that without the parentheses, the expression means “the negative of ‘3 squared’ that is, the exponent is applied before the negative sign.
  19. T OR F
    All positive numbers have two square roots, one positive and one negative.
    TRUE.

    THE SQUARE ROOT OF 0 IS 0.
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Author
shockwave
ID
270897
Card Set
MATH TIDBITS FOR GRE ONE
Description
MATH TIDBITS FOR GRE ONE
Updated