Introduction to Comp菓ex Numbers
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Lea「niれg Targets:
● Know the definition ofthe complex number f.
Know that complex numbers can be written as cz + bi, Where a and1bare S, Write し魚cance. .atthe that 京Ve 竜合軒 亡ician G彬at、功 legative 鼻tion ⊃ し,宜rst r 1at 1Ct21:’ 十∴lO∴ 9ニ8l 0-高二 ∴:∴:∴:∴
real numbers.
● Graph complex numbers on the complex plane.
SUGGESTED LEARNING STRATEGIES: Create Representations
Interactive Word Wall, Marking the耽xt, Think-Pair-Share, Quickvr
The equation x2 + 1 = O has special historical and mathematical signi
At the beginning of the sixteenth century, mathematicians believed th
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A breakthrough occurred in 1545 when the talented Italian mathe m at
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Girolamo Cardano (150l-1576) published his book, AγS M讐na (了坊e
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encountered-and was required to make use ofLthe square roots
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numbers. While skeptical of their existence, he demonstrated the
With this famous problem: Find two numbers with the sum lO and
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2. Make sense of p「oblems. Tb better understand this problem
find two numbers with the sum 10 and the product 21.
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3. Letting x represent one number, Write an expression for the
number in terms ofx. Use the expressions to write an equation
models the problem in Item 2: f屯nd two numbers with the
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A⊂tivity8o introduction to Complex Numbers 121
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the imaginary unit. Ybu can say i = √i. The imaginary unit f is
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the solution to the equation j2 + 1 = 0, Or i2 = -1.
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The set ofcomplex numbers consists ofthe real numbers and the imaginary
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a complex number and the vertical axis representing the imaginary part bi of
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Graph each complex number on a complex plane grid・
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124 SpringBoard⑪ Mathematics Algebra2, Unit2. Quadratic Functions
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21. Draw the complex plane. Then graph each complex
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