More with Complex Numbers
ex A:
2 + 3i would be graphed
as the point (2, 3)
ex B:
4 - i would be graphed
as the point (4, -1)
imaginary
• graphing: a complex number , a+bi, can be
graphed as the coordinate (a, b)
• the x- axis represents real numbers while the yaxis represents imaginary
A
real
B
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Absolute Value
Graph These:
a) 2 + 5i
the absolute value of a complex number is the LENGTH OF
THE VECTOR from (0, 0) to (a, b)
To find length on the coordinate plane we use the distance
formula or Pythagorean Theorem
b) -3 + i
c) 1 - 3i
d) -5 - 3i
ex: |2 + 5i|
Find These:
e) 2i
b)| -3 + i|
f) 3
c) |1 - 3i|
d) |-5 - 3i|
e) |2i|
f) |3|
Dec 6­9:59 AM
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Identity Properties
the additive identity element of a real number is ___
the multiplicative identity element of a real number is ___
the additive identity element of a complex number is:
(a + bi) + (_____) = (a + bi)
the multiplicative identity element of a complex number is :
Find the additive and multiplicative inverse of
(a + bi) (____) = a + bi
-2 + 2i
Inverse Properties
the additive inverse for a real number, x, is____
ex. 5 + ___ = 0
the additive inverse for a complex number, ax + bi, is_____
ax + bi + (______) = 0 + 0i
ex. find the additive inverse of
-2 + 3i
the multiplicative inverse of a number, x, is ___
ex. 5 (1/5) = 1
the multiplicative inverse of a complex number, a + bi, is _____
ex. find the multiplicative inverse of 5 + 7i
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