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McGraw Hill Integrated II, 2012

MH

McGraw Hill Integrated II, 2012 View details

Mid-Chapter Quiz

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Exercise 18 Page 188

Recall that the imaginary number i is a complex number whose square is - 1.

9i

We want to simplify the given numeric expression. To do so, we will first recall that the imaginary unit i is a complex number whose square is - 1. i^2=- 1 and i=sqrt(- 1) We can simplify the expression using this definition.

sqrt(- 81)

SplitIntoFactors

Split into factors

sqrt(- 1* 81)

sqrt(a* b)=sqrt(a)*sqrt(b)

sqrt(- 1)* sqrt(81)

sqrt(- 1)= i

i* sqrt(81)

Calculate root

i* 9

CommutativePropMult

Commutative Property of Multiplication

9i