Find the product of the complex numbers and enter it below. Remember that i = .

(4 - i )(1 + 4i )

Question

Find the product of the complex numbers and enter it below. Remember that i = .

(4 - i )(1 + 4i )

neonumbrella5115 · Answer

Have you tried FOILing?

anonymous · Answer

no i haven't @neonumbrella5115  i dont know how to do this at all

neonumbrella5115 · Answer

Okay so to FOIL you would multiply each term in the first parenthesis with both terms in the second parentheses.  Then you would multiply the second term in the first parentheses by each term in the second parentheses.  The add all those values.
Example will follow.

anonymous · Answer

$$\left( 4-i \right)\left( 1+4i \right) =(4+15i-4i^2)$$

triciaal · Answer

use the distributive property twice 
also commonly referred to as FOIL because of the steps in the operation

for complex numbers remember that i^2 = -1

anonymous · Answer

now you know that i=squrt(-1) and i^2=-1

neonumbrella5115 · Answer

4*1=4
4*4i=16i
-1i*1=-i
-i*4i=-4i^2
Add those numbers together now.  Then because i^2 is 1, plug that in as i^2

triciaal · Answer

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