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Pearson Algebra 2 Common Core, 2011

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Pearson Algebra 2 Common Core, 2011 View details

Cumulative Standards Review

Exercise 17 Page 356

Recall that i^2=- 1 and sqrt(- 1)=i.

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Practice makes perfect

We can simplify the given expression by combining like terms. Recall the definition of the imaginary unit i.

sqrt(-1)=i and -1=i^2

Now we can multiply the expressions.

(2+i)(2-i)

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Distribute

Distribute (2+i)

(2+i)2-(2+i)i

Distribute 2

4+2i-(2+i)i

Distribute i

4+2i-(2i+i^2)

Distribute -1

4+2i-2i-i^2

i^2=- 1

4+2i-2i-(-1)

a-(- b)=a+b

4+2i-2i+1

Add and subtract terms

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