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Chapter 7. 7.1 Radical Expression. Theorem 7.1. Every positive real number has two real number square roots 0 has just one square root: 0 Negative numbers do not have real number square roots. Principal Square Root.
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Chapter 7 7.1 Radical Expression
Theorem 7.1 • Every positive real number has two real number square roots • 0 has just one square root: 0 • Negative numbers do not have real number square roots
Principal Square Root • The Principal Square Root of a non-negative real number is its non-negative root.
This symbol is a radical sign • An expression written with a radical sign is a radical expression • The expression written under the radical sign is the radicand
Radical Expression Index Radicand Radical
Absolute Value • For any real number a, • The principal square root of a2 is the absolute value of a.
Chapter 7 7.2 Multiplying and Simplifying
Chapter 7 7.3 Operations with Radical Expressions
Chapter 7 7.4 More Operations with Radical Expressions
Chapter 7 7.5 Rational Numbers as Exponents
Theorem 7.6: For any nonnegative number a, any natural number index k, and any integer m,
Definition: For any nonnegative number a and any natural number index k, means (the nonnegative kth root of a) Note: When working with rational exponents, we will assume that variables in the base are nonnegative
Definition: For any natural numbers m and k, and any nonnegative number a, means
Definition: For any rational number and any real number a, means
Chapter 7 7.6 Solving Radical Equations
Note: When solving a radical equation it is sometimes necessary to isolate the radical and use the inverse operation more than once
Chapter 7 7.7 Imaginary and Complex Numbers
Solve: x2 + 1 = 0 In the real number system negative numbers do not have square roots, therefore there is no real solution. x2 = -1 Mathematicians invented imaginary numbers so negative numbers would have square roots Thus the solution to the above equation would be
Definition: The imaginary numbers consist of all numbers bi, where b is a real number and i is the imaginary unit, with the property that i2 = -1 Pattern Recognition Using the information from above, write a general statement about the standard form of in where n is a positive integer. Use this statement to write i231in standard form.
When operating on imaginary numbers: 1. Always take the i out of the radical first 2. Treat i as a variable 3. Never write i with a power greater than 1
Definition: The complex numbers consist of all sums a + bi, where a and b are real numbers and i is the imaginary unit. The real part is a and the imaginary part is bi. All real numbers are complex numbers We assume that i behaves like a real number, that is it obeys all the rules of real numbers
Chapter 7 7-8 Complex Numbers and Graphing
Remember a complex number has a real part and an imaginary part. These are used to plot complex numbers on a complex plane. Imaginary Axis The absolute value of z denoted by |z| is the distance from the origin to the point (x, y). z b RealAxis a
Plot the number in the complex plane and then find the absolute value of the complex number.
Plot the number in the complex plane and then find the absolute value of the complex number.