November 20, 2013
3.8 Finding and Estimating Square Roots
Inverse Operations:
Square Root: The number a is a square root of b if
a2 = b
(-4)2 =
Ex: 4 2 =
Principal Square Root:
Negative Square Root:
Radicand:
Ex: Simplify each expression
1. √36
4. √-49
3.
2. ±√64
5.
9
-√ 25
1
√ 64
Rational and Irrational:
Rational
Irrational
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November 20, 2013
Ex 2: Tell whether each expression is rational or irrational
1. ±√144
4.
1
√9
2.
-√ 51
3. -√ 6.25
5. √7
Estimating and Using Square Roots
Perfect Squares -
Ex 3: Between what 2 consecutive integers is √28.34?
Between what 2 consecutive integers is √51.29?
Approximating Using a Calculator
Ex 4: Find √28.34 to the nearest hundredth.
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November 20, 2013
Guided Practice
1. Simplify each expression
a. √81
b.±√100
c.
-√
1
25
2. Tell whether each expression is rational or irrational.
c. -√75
b. ±√225
a. √8
3. Between what 2 consecutive integers is -√105?
4. Between what 2 consecutive integers is √191?
5. Find √17.81 to the nearest hundredth.
Homework:
Pages 178-179 # 2-16 even, 18-22, 26-36, 41-47 odd
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