Section 8.1 Laws of Exponents: Multiplying monomials Algebra I Obj: define exponents and powers. Obj: find products of powers. Obj: simplify products of monomials. Vocab Base of a power the # that is raised to an exponent. In an expression of the the form xa, x is the base. Coefficient a # that is multiplied by a variable. Exponent in a power, the # that tells how many times the base is used as a factor. In an expression of the form xa, a is the exponent. Monomial an algebraic expression that is either a constant, a variable, or a product of a constant and one or more variables. Product of powers property if x is any # and m and n are intergers, then xm . xn = xm+n xm xn = xm+n Simplify the product of monomials containing exponents. Simplify (5c2d3)(7cd5) Group terms with the same base. = 35 c2 c d3 d5 Use the Product-of-Powers Property. = 35 c2 + 1 d3 + 5 Simplify = 35c3d8 Section 8.2 Laws of Exponents: powers and products Obj: Find the power of a power. Obj: Find the power of a product. Vocab Power of a power property if x is any # and m and n are integers, then (xm)n Power of a product property if x and y are any # and n is an integer, then (xy)n = xnyn Use the properties of exponents to simplify an expression. Simplify n3(2k2n4)2 = n3 22 (k2)2(n4)2 Use the Power-of-a-Power Property. = n3 4 k2(2) n4(2) = n3 4 k4 n8 Use the Product-of-Powers Property. = 4 k4 n3+8 = 4k4n11 Powers of –1 Even powers of –1 are equal to 1. Odd powers of –1 are equal to –1. Algebra I Section 8.3 Laws of Exponents: Dividing Monomials Algebra I Obj: simplify quotients of powers. Obj: simplify powers of fractions. Vocab Power of a fraction property if n is an integer and a and b are #s, where b ≠ 0, then (a/b)n = an/bn Quotient of powers property if x is any # except 0 and ma and n are any positive integers, where m > n then xm/xn = xm-n Use the properties of exponents to simplify expressions containing fractions. 15x7y3 3xy2 Use the Quotient-of-Powers Property. = 5x6y Use the properties of exponents to simplify expressions containing fractions. Use the Power-of-a-Fraction Property. Section 8.4 Negative and Zero Exponents Obj: Understand the concepts of negative and zero exponents. Obj: Simplify expressions containing negative and zero exponents. Vocab Negative exponent if x is any # except zero and n is a positive integer, then x-n = 1/xn Zero as an exponent for any nonzero # x, x0 = 1 Simplify expressions containing negative and zero exponents. and write the expression with positive exponents only. = 7 x3 – 8 y2 – 1 z1 – 3 = 7x–5yz–2 Algebra I Section 8.5 Scientific Notation Algebra I Obj: recognize the need for special notation in scientific calculations. Obj: perform computations involving scientific notation. Vocab Scientific notation a # written in scientific notation is a product of 2 factors: a # from 1 to 10, including 1 but not including 10 and a power of 10. Perform computations involving scientific notation. Write (4 104)(7 105) in scientific notation. = 28 109 = (2.8 101)(109) = 2.8 1010 Section 8.6 Exponential Functions Algebra I Obj: understand exponential functions and how they are used. Obj: recognize differences between graphs of exponential functions with different bases. Vocab Exponential function a function of the form y = 2x in which a base # is raised to a variable exponent. Exponential functions model situations in which values in the range change by a fixed rate rather than a fixed amount. General growth formula Let A be the amount after t years at a yearly growth rate of r, where r is expressed as a decimal. If the original amount is P, then the general growth formula is A=P(1+r)t A = original amount t = time in years r = yearly growth rate expressed as a decimal P = amount after t years Understand and graph exponential functions. The current population of a city is 275,000. It is estimated that the population will grow at a rate of 2.2% per year. What will the population be 6 years from now? A = 275,000 P = A(1 + r)t r = 0.022 P = 275,000(1.022)6 t=6 P 313,356 Section 8.7 Applications of Exponential Functions Algebra I Obj: use exponential functions to model applications that include growth and decay in different contexts. Vocab Exponential decay a situation modeled by the general growth formula, A =P(1+r)t, in which r is negative. Exponential growth a situation modeled by the general growth formula, A = P(1+r)t, in which r is positive. Use exponential functions to model applications. The current population of a city is 403,000. Over the last 10 years, the population has been decreasing at the rate of 1.6% per year. What will the population be 6 years from now? A = 403,000 P = A(1 + r)t r = 1 – 0.016 P = 403,000(0.984)6 t=6 P 365,827