McGraw Hill Integrated II, 2012
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McGraw Hill Integrated II, 2012 View details
3. Simplifying Radical Expressions
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Exercise 9 Page 248

For radical expressions where the exponent of a variable inside the radical is even and the simplified expression has an odd exponent, absolute value symbols must be used.

3b^2|c|sqrt(11ab)

Practice makes perfect
Before we attempt to simplify the given radical expression, let's consider one of the more difficult parts of correctly simplifying radicals. When the exponent of a variable inside the radical is even and the simplified expression for that variable has an odd exponent, we need to use absolute value symbols. ll sqrt(x^2)= |x| & sqrt(x^3)=x sqrt(x) sqrt(x^4)= x^2 & sqrt(x^6)=|x^3| This is because we do not want the result to be negative — the range of a square root function is all real numbers greater than or equal to 0. Now, consider the given radical expression. sqrt(99ab^5c^2) The exponent of b is odd, so we will not need absolute value symbols when we remove b from the radical. The exponent of c is even and, in the simplified expression, this variable will have an odd exponent. Therefore, when we remove c from the radical, we will need absolute value symbols.
sqrt(99ab^5c^2)
sqrt(9(11)ab^5c^2)
sqrt(3^2(11)ab^5c^2)
sqrt(3^2(11)ab^(1+4)c^2)
sqrt(3^2(11)abb^4c^2)
Now that we have simplified the factors as much as possible, let's recall the Product Property of Square Roots. sqrt(a* b)=sqrt(a) * sqrt(b), for a≥ 0,b≥ 0 Let's use this property to simplify our expression even further.
sqrt(3^2(11)abb^4c^2)
sqrt(3^2b^4c^2(11)ab)
sqrt(3^2)sqrt(b^4)sqrt(c^2)sqrt(11ab)
sqrt(3^2)sqrt(b^(2(2)))sqrt(c^2)sqrt(11ab)
sqrt(3^2)sqrt((b^2)^2)sqrt(c^2)sqrt(11ab)
3b^2sqrt(c^2)sqrt(11ab)
3b^2|c|sqrt(11ab)