Presentation on theme: "Start thinking of math as a language, not a pile of numbers"— Presentation transcript:
1 Start thinking of math as a language, not a pile of numbers Just like any other language, math can help us communicate thoughts and ideas with each otherAn expression is a thought or idea communicated by languageIn the same way, a mathematical expression can be considered a mathematical thought or idea communicated by the language of mathematics.Mathematics is a language, and the best way to learn a new language is to immerse yourself in it.A SSE 1
2 Just like English has nouns, verbs, and adjectives, mathematics has terms, factors, and coefficients.Well, sort of.TERMSare the pieces of the expression that are separated by plus or minus signs, except when those signs are within grouping symbols like parentheses, brackets, curly braces, or absolute value bars.Every mathematical expression has at least one term.Has two terms.A term that has no variables is often called a constant because it never changes.
3 Within each term, there can be two or more factors. The numbers and/or variables multiplied together.Has two factors: 3 and x.There are always at least two factors, though one of them may be the number 1, which isn't usually written.Finally, a coefficient is a factor (usually numeric) that is multiplying a variable.Using the example, the 3 in the first term is the coefficient of the variable x.
4 The order or degree of a mathematical expression is the largest sum of the exponents of the variables when the expression is written as a sum of terms.Order is 1Since the variable x in the first term has an exponent of 1 and there are no other terms with variables.Order is 2Order is 5
5 Now that we have our words, we can start putting them together and make expressions Translate mathematical expressions into English"the sum of 3 times a number and 2,""2 more than three times a number"It's much easier to write the mathematical expression than to write it in English
7 Practice 1.1 Variables and Expressions A-SSE.A.1
8 Practice 1.1 Variables and Expressions A-SSE.A.1
9 Just the facts: Order of Operations and Properties of real numbers A GEMS/ALEX SubmissionSubmitted by: Elizabeth Thompson, PhDSummer, 2008
10 Important things to remember Parenthesis – anything grouped… including information above or below a fraction bar.Exponents – anything in the same family as a ‘power’… this includes radicals (square roots).Multiplication- this includes distributive property (discussed in detail later).Some items are grouped!!!Multiplication and Division are GROUPED from left to right (like reading a book- do whichever comes first.Addition and Subtraction are also grouped from left to right, do whichever comes first in the problem.Click to extend information
11 So really it looks like this….. ParenthesisExponentsMultiplication and DivisionAddition and SubtractionIn order from left to rightIn order from left to rightClick to extend information
12 SAMPLE PROBLEM #1 Parenthesis Exponents This one is tricky! Remember: Multiplication/Division are grouped from left to right…what comes 1st?Division did…now do the multiplication (indicated by parenthesis)Click and the operation / next step will appear…keep clicking until the end.More divisionSubtraction
13 SAMPLE PROBLEM Exponents Parenthesis Click and the operation / next step will appear…keep clicking until the end.Remember the division symbol here is grouping everything on top, so work everything up there first….multiplicationDivision – because all the work is done above and below the lineSubtraction
14 Order of Operations-BASICS Think: PEMDAS Please Excuse My Dear Aunt Sally ParenthesisExponentsMultiplicationDivisionAdditionSubtractionClick to extend information
15 Practice 1.2 Order of Operations and Evaluating Expression A-CED.1
16 Practice 1.2 Order of Operations and Evaluating Expression
17 Practice 1.2 Order of Operations and Evaluating Expression
18 Practice 1.2 Order of Operations and Evaluating Expression
20 Lesson Extension Can you fill in the missing operations? 2 - (3+5) = -2* 3 ÷ 3 = 115 * ÷ 2 = 10Teachers: One location for worksheets with ‘blank’ operations isFor an extension of this slide, have each student fold a paper like a card. On the cover of the card, they create a problem with blanks (like the slide) on the inside of the card is the solution. On the back of the card is their name (like you would find a label on a real card). This can be done as homework or a classroom extension.
25 Properties of Real Numbers (A listing) Associative PropertiesCommutative PropertiesInverse PropertiesIdentity PropertiesDistributive PropertyClick for examples of eachAll of these rules apply to Addition and Multiplication
26 Associative Properties Associate = group It doesn’t matter how you group (associate) addition or multiplication…the answer will be the same!Rules:Associative Property of Addition(a+b)+c = a+(b+c)Associative Property of Multiplication(ab)c = a(bc)Samples:Associative Property of Addition(1+2)+3 = 1+(2+3)Associative Property of Multiplication(2x3)4 = 2(3x4)Later we will discuss how these do not apply to subtraction and division.
27 Commutative Properties Commute = travel (move) It doesn’t matter how you swap addition or multiplication around…the answer will be the same!Rules:Commutative Property of Additiona+b = b+aCommutative Property of Multiplicationab = baSamples:Commutative Property of Addition1+2 = 2+1Commutative Property of Multiplication(2x3) = (3x2)The next slide will discuss how these do not apply to subtraction and division.
28 Is (5-2)-3 = 5-(2-3)? Is (6/3)-2 the same as 6/(3-2)? Stop and think!Does the Associative Property hold true for Subtraction and Division?Does the Commutative Property hold true for Subtraction and Division?Is (5-2)-3 = 5-(2-3)? Is (6/3)-2 the same as 6/(3-2)?Leave time to discuss prior to clicking examples.Is 5-2 = 2-5? Is 6/3 the same as 3/6?Properties of real numbers are only for Addition and Multiplication
29 Inverse Properties Think: Opposite What is the opposite (inverse) of addition?What is the opposite of multiplication?Subtraction (add the negative)Division (multiply by reciprocal)Rules:Inverse Property of Additiona+(-a) = 0Inverse Property of Multiplicationa(1/a) = 1Samples:Inverse Property of Addition3+(-3)=0Inverse Property of Multiplication2(1/2)=1
30 Identity Properties Rules: a+0 = a a(1) = a Samples: 3+0=3 2(1)=2 What can you add to a number & get the same number back?What can you multiply a number by and get the number back?0 (zero)1 (one)Rules:Identity Property of Additiona+0 = aIdentity Property of Multiplicationa(1) = aSamples:Identity Property of Addition3+0=3Identity Property of Multiplication2(1)=2
31 Distributive Property If something is sitting just outside a set of parenthesis, you can distribute it through the parenthesis with multiplication and remove the parenthesis.Rule:a(b+c) = ab+bcSamples:4(3+2)=4(3)+4(2)=12+8=202(x+3) = 2x + 6-(3+x) = -3 - xDiscuss/illustrate how arrows can help a student stay on track