Question

Find each absolute value.
l 4 + 2i l

Answer 1

\[|a+bi|=\sqrt{a^2+b^2}\]

Answer 2

forget negative numbers, forget \(i\) just compute \(\sqrt{a^2+b^2}\) with
\[a=4,b=2\]

Answer 3

what about the imaginary numbers though?

Answer 4

what about them?

Answer 5

like i said, ignore all minus signs and the \(i\)
the absolute value is a positive real number, the distance that your complex number is from the origin
by pythagoras, it is \(\sqrt{a^2+b^2}\)
i can draw a picture if you like

Answer 6

No it's fine, thankyou!

Answer 7

Would the absolute value of l 5 - i l be 5? & ohh okaay I got it :)

Answer 8

@satellite73

Answer 9

no no not 5

Answer 10

it is
\[\sqrt{5^2+1^2}=\sqrt{26}\]

Answer 11

when i said "forget the \(i\) " i did not mean pretend it is not there, i meant don't include it in your calculations
this is the same as \(5-1i\) so you use 5 and 1

Answer 12

OK Thankyou! :)

Answer 13

yw