Properties of Real Numbers:

  1. Listed below are several properties of real numbers. Give an example of each of the properties.
  2. i. Commutative Property of Addition

    a + b = b + a i______________________

  3. Solve.
    1. = 12x=_________

= 0 x=_________

  1. Recall, |a| = 7 means that a is either 7 or it is –7. Likewise, |a + 5 | = 7 means (a + 5) is equal to 7 or (a + 5) is equal to –7. This implies that a = 2 or a = -12. Solve for x:
    1. |x + 3| = 8x=_________

 

Coordinate System

  1. Determine whether the points given are solutions to the following equations, (i.e., does the point given lie on the graph of the equation?).
    1. y = 2x – 9(1, 2)Yes / No
  1. Find the length of the segment joining the given points, i.e. find the distance, d, between the following points. Then find the midpoint, M, of the segment. Recall, d=and M=

.

    1. (1, 2) & (4, 5).
  1. The point-slope form of a linear equation is y – y1 = m(x –x1). Using the point-slope form, write an equation of the line that passes through the given point P(x1, y1) and has the given slope, m. Simplify the equation and rewrite it in slope-intercept form, y = mx + b.
    1. P(1, 2) , m=½
  1. Using the point-slope form, write an equation of the line that passes through the given points (x1, y1) & (x2, y2). Simplify.
    1. (2, 3) & (4, 6) ______________

 

 

Inequalities with two variables.

  1. Graph the following inequalities.
    1. 3x + 2y ³ 12

wpe17.jpg (24132 bytes)

 

  1. Given an equation of a parabola of the form, f(x) = y = a(x – h)2 + k, we have that (h, k) is the vertex …

Give the vertex of the following parabolas.

    1. y = x2 – 6x – 1 (_____,_____)
  1. Graph the following parabolas.
    1. y = x2 – 6x + 12
  1. Solve for the indicated variable.
  1. ax + by = c for xx=______________
  2. C = 2p r for rr=______________
  3. y = mx + b for bb=______________
  4. V = 2p r2 + 2p rhfor hh=______________

 Exponents & Radicals

Some properties of exponents and radicals.

i. an × am = an+m

  1. =

Example #4:

Simplify.

====.

Example #5:

====

  1. Simplify.
  1. =______________
  2. =______________

= ______________

Rationalizing

When working with radicals, we never leave a radical in the denominator of a fraction. …

  1. Solve.
    1. = 5x = _____________
    2. - 4 = 5x = _____________
    3. 5x – 30

+ 45 = 0 x = _____________

Polynomials

Perfect Square Trinomials (a + b)2 = a2 + 2ab + b2

Difference of Squares a2 – b2 = (a + b)(a – b) …

  1. Add or Subtract the following polynomials by combining like terms.
    1. (x3 + 3x2 – 4x + 4) + (4x3 – 9x2 – 5x + 3)
  1. Multiply the following polynomials.
    1. (3x3 – x2 + 2x – 4)(x2 – 5x + 3) ____________________________________
  1. Expand (3x + 7y)2.____________________________________
  2. Factor completely:
    1. 2x2 – x – 6 ____________________________________
  1. Factor completely. (Hint: for some try using special formulas.)
    1. 49x2 – 25y2____________________________________
    2. (m2 + 18m + 81) – (n2 + 4n + 4)____________________________________
  1. Simplify.
  1. _________________

 Solving Rational Equations.

When solving rational equations, one must check answers for extraneous solutions. In other words, one must check to make sure the answers obtained are in the domain of the rational expressions (the denominator of the rational expressions cannot equal zero).

  1. Solve for x.
    1. =
  1. x =______

Word Problems

  1. Seven times a number is the same as twelve more than three times the number. Find the number.
  2. Find two consecutive integers whose sum is –29.
  3. The sum of the reciprocals of two consecutive integers is .
  4. Jonathan hiked up 10.5km on a trail on Longs Peak. It took him ½ hour less on the return trip since when coming down the mountain, he increased his speed by ½km/h. How long did it take him to hike up and down the mountain trail? (Hint: do not convert hrs to min. as units of time)
  5. y varies directly as x and y = 48 when x = 3. What is y when x = 12?
  6. If a chemist starts with 15cm3 of a 20% saline solution, how many cubic centimeters of water must she add to obtain a 10% saline solution?

        wpe15.jpg (5397 bytes)

  1. Find the area of square A._____________________
  2. Find the area of rectangle C & D._____________________

Imaginary Numbers

i = i2 = ()2 = -1 i3 = ()3 = ()2() = -1()= -i

Zero Product Property

ab = 0 means a = 0 or b = 0.

I.e. if you have two numbers whose product is zero, one of them has to equal 0.

So, if given (x – 3)(x – 2) = 0, we have that a = x – 3 and b = x – 2 and either a or b equaling zero would make the product zero. Therefore, either

a = x – 3 = 0 or b = x – 2 = 0 which implies that either

x = 3 or x = 2.

 

This only works if the product ab = 0! If ab = 4, there are several numbers that can be multiplied to get 4 (2 and 2, 1 and 4, ½ and 8 to name a few). Therefore, it is vital that one does not make the following mistake:

x2 – 4x = 4

x(x – 4) = 4 means

x = 4 or x – 4 = 4 WRONG, WRONG, WRONG!

...

Factoring Tips …

Factoring by grouping:

Factoring using the "trial-and-error method."

Factoring using the "dream method"

Try it!

Factor 6x2 + 11x – 10 using both the trial and error method and the dream method.

Using Pascal’s Triangle to expand (a + b)n: …

Working with matrices.

The dimensions of a matrix are always given as "# rows x # columns." For, example, the matrix is a 3 x 2 matrix, while is a 2 x 3 matrix. …

1.1 What is geometry?

Geometry is the study of points, lines, angles and all of the objects that can be made of points, lines, and angles. There are different kinds of geometries. In this book, we will study Euclidean geometry, also known as parabolic geometry. There are non-Euclidean geometries such as hyperbolic geometry and elliptic geometry. Other names of geometries include: projective geometry, spherical geometry, algebraic geometry, fractal geometry, etc.

Why are there so many different geometries? Each geometry deals with different characteristics and/or properties. In Euclidean geometry, one works with straight lines, circles, and arcs (fractions/parts of circles) which is fine if one is building a desk with straight lines or other objects we own.

However, when we are working on the flight paths of our jet airliners, we need to work with a geometry without straight lines. Notice that airplanes do not travel in straight lines around the Earth, nor do satellites orbiting the earth, (see below). We would then work with a non-Euclidean geometry.

  Images from NASA 

      1. What is a geometry? _______________________________________________________________
      2. _____________________________________________________________________________________

      3. Why do we need different geometries? _________________________________________________

_____________________________________________________________________________________

In order to well understand the other geometries, it is best to first grasp a strong understanding of Euclidean geometry.

 

SAN Problems (Sometimes Always Never Problems)

Directions: Write "S" in the blank if the statement given is sometimes true, "A" if the statement is always true, or "N" if the statement is never true. Sometimes it is helpful to use a penny as a point, a pencil as a line, and an index card for a plane to visualize the statements given. Rotate these objects and see if you can create the situations given with them.

    1. Three points are collinear.__________________
    2. Three points determine a plane.__________________
    3. Three non-collinear points determine a plane.__________________
    4. If two coplanar points determine a line, the line lies in the plane.__________________
    5. If one point is in a plane, a line passing through that point is also in the plane._________________
    6. Given a point and a line, one can draw a line through the point parallel to the line._____________