McGraw Hill Integrated II, 2012
MH
McGraw Hill Integrated II, 2012 View details
1. Geometric Mean
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Exercise 54 Page 627

For any two positive numbers a and b, the geometric mean is the positive number x such that ax= xb .

A

Practice makes perfect
For any two positive numbers a and b, the geometric mean is the positive number x such that ax= xb. Since we know that x must be positive, the following equation is the definition of a geometric mean. x= sqrt(a b)We are asked to find the geometric mean of the given pair of numbers. 8 and 22 Let's substitute them into the equation and simplify the right-hand side to find the mean x.
x=sqrt(8* 22)
â–Ľ
Evaluate
x = sqrt(4 * 2 * 2 * 11)
x = sqrt(4 * 4 * 11)
x = sqrt(4) * sqrt(4) * sqrt(11)
x = 2 * 2 * sqrt(11)
x= 4sqrt(11)
We can see that the obtained value corresponds to option A.