Lesson 7-1: Radical Expressions

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Lesson 7-1Radical Expressions

• Objectives
• Students will
• Find square roots of numbers
• Find n-th root of numbers

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Square Root The square root of a is c if c2 a
? if There are 2 square roots
of positive numbers c2 a and (-c)2 a
Example 1 Find the square roots of
each 49 225
Principle Square Root ,when the positive
square root is wanted Negative Square Root
,when the negative square root is wanted
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Radicals is called a radical sign Any
expression with this sign is a radical
expression The expression under the is
the radicand
Radical Property The square root of a perfect
square is the absolute value of the value being
squared (principle square root)
Example 2
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N-th Roots means c3 a ? c is the
cube root Can have 4th roots, 5th roots,.
is the n-th root of a number
Activity - Find the following Is there a
pattern with the answers and the n-value?
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N-th Root Property
, when n is even (always )
, when n is odd (can be or -)
, does not exist when n is even
Determine domain of a root.
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• Examples
• Give the roots of 169
• Simplify
• Simplify
• Simplify
• Simplify
• 8) Find domain

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assignment

• 7-1/295-296/ 2-64e