[size=150]Which expression is equivalent to [math]2i(5+3i)[/math]?[/size]
[size=150]Lin says, “When you add or multiply two complex numbers, you will always get an answer you can write in [math]a+bi[/math] form.”[br][br]Noah says, “I don’t think so. Here are some exceptions I found:”[/size][br][br][math](7+2i)+(3-2i)=10[/math][br][br][math](2+2i)(2+2i)=8i[/math][br][br]Check Noah’s arithmetic. Is it correct?[br]
Can Noah’s answers be written in the form [math]a+bi[/math], where [math]a[/math] and [math]b[/math] are real numbers? Explain or show your reasoning.[br]
Explain to someone who missed class how you would write [math](3-5i)(\text{-}2+4i)[/math] in the form [math]a+bi[/math], where [math]a[/math] and [math]b[/math] are real numbers.
Which expression is equal to [math]729^{\frac{2}{3}}[/math]?
[math]2x^2-\frac{2}{3}=5\frac{1}{3}[/math]
[list][*][math]5i[/math][/*][*][math]2+4i[/math][/*][*][math]-3[/math][/*][*][math]1-3i[/math][/*][*][math]\text{-}5-2i[/math][/*][/list]
Select [b]all[/b] the expressions that are equivalent to [math](3x+2)(x-4)[/math] for all real values of [math]x[/math].