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Daily Check:. Perform the indicated operation . Find the area and perimeter of the box . 3. Perimeter = ____ 4. Area = ____. 2x-3. 2x+1. Homework Review. CCGPS Analytic Geometry Day 32 (9-20-13). UNIT QUESTION: In what ways can algebraic methods be used in problem solving?
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Daily Check: Perform the indicated operation. Find the area and perimeter of the box. 3. Perimeter = ____ 4. Area = ____ 2x-3 2x+1
CCGPS Analytic GeometryDay 32 (9-20-13) UNIT QUESTION: In what ways can algebraic methods be used in problem solving? Standard: MCC9-12.N.RN.1-3, N.CN.1-3, A.APR.1 Today’s Question: How do we take the square root of negative numbers? Standard: MCC9-12..N.CN.1-3
A long long time ago, in a math class far, far away.. There was no way to take the square root of a negative number
Every time we squared a negative number We got a positive.
(-1) = 1 (-2) = 4 (-3) = 9
Was there a number, that when multiplied by itself Gave you a negative???
Can we in fact, take the square root of a negative number? WE CAN!!!!
Ladies and Gentlemen of Math II I present to you a NEW number... A number so complex...
It stretches the imagination.. I present to you:
You can't take the square root of a negative number, right? • When we were young and still in Math I, no numbers that, when multiplied by themselves, gave us a negative answer. • Squaring a negative number always gives you a positive. (-1)² = 1. (-2)² = 4 (-3)² = 9
So here’s what the math people did: They used the letter “i” to represent the square root of (-1). “i” stands for “imaginary” So, does really exist?
*For larger exponents, divide the exponent by 4, then use the remainder as your exponent instead. Example:
$25,000 Pyramid i 1 -i -1 i -i -1 -i 1 -1
$25,000 Pyramid i -i -1 -1 -i i -1 -i 1 -i
Complex Numbers • A complex number has a real part & an imaginary part. • Standard form is: Real part Imaginary part Example: 5+4i
The Complex Plane Real Axis Imaginary Axis
Adding and SubtractingAdd or subtract the real parts, and then, add or subtract the imaginary parts. Ex: Ex:
MultiplyingTreat the i’s like variables, then change any that are not to the first power Ex: Ex:
Conjugates: Two complex numbers of the form a + bi anda – bi are complex conjugates. The product is always a real number Ex:
Conjugates: Two complex numbers of the form a + bi anda – bi are complex conjugates. The product is always a real number Ex:
Conjugates:Two complex numbers of the form a + bi anda – bi are complex conjugates. The product is always a real number
Dividing Complex Numbers • Multiply the numerator and denominator by the conjugate of the denominator. • Simplify completely.
Assignment Complex Numbers Practice WS