Mathematics
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OpenStudy (anonymous):
Express the complex number in trigonometric form.
-3 + 3 square root of three i
11 years ago
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jimthompson5910 (jim_thompson5910):
I'm assuming the expression given is \(\Large -3+3\sqrt{3}*i\)
If so, then it's the same as last time but now
\[\Large a = -3\]
\[\Large b = 3\sqrt{3}\]
11 years ago
OpenStudy (anonymous):
yeah, that is the correct expression
11 years ago
OpenStudy (plasmataco):
quick question... what is the square root of i?
11 years ago
OpenStudy (plasmataco):
I know... im a little slow with the noggin but still...
11 years ago
jimthompson5910 (jim_thompson5910):
the i isn't part of the square root
11 years ago
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OpenStudy (plasmataco):
i know, just curios.
11 years ago
OpenStudy (anonymous):
-1
11 years ago
OpenStudy (plasmataco):
...
11 years ago
OpenStudy (plasmataco):
i thought that was the square... exponent 2.
11 years ago
OpenStudy (plasmataco):
-1*-1=1 not i.
11 years ago
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jimthompson5910 (jim_thompson5910):
\[\Large i = \sqrt{-1}\]
\[\Large i^2 = (\sqrt{-1})^2\]
\[\Large i^2 = -1\]
11 years ago
OpenStudy (anonymous):
\[\iota ^{2} = -1\]
11 years ago
OpenStudy (plasmataco):
am i just the stupid idiot here or u genuinely dont know or connection problemos?
11 years ago
OpenStudy (plasmataco):
square root. sry like radical.
11 years ago
jimthompson5910 (jim_thompson5910):
sorry @Plasmataco I'm not following
11 years ago
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OpenStudy (plasmataco):
i know but like -1 under a radical of 4
11 years ago
jimthompson5910 (jim_thompson5910):
were you able to find r and theta, @lxoser ?
11 years ago
OpenStudy (plasmataco):
...
11 years ago
jimthompson5910 (jim_thompson5910):
oh you mean
\[\Large \sqrt{i} = \sqrt[4]{-1}\] @Plasmataco ??
11 years ago
OpenStudy (plasmataco):
\[\sqrt[4]{-1}\]
11 years ago
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OpenStudy (plasmataco):
yeah
11 years ago
OpenStudy (anonymous):
im gonna need help finding r and theta @jim_thompson5910
11 years ago
OpenStudy (plasmataco):
sry for interrupting...
11 years ago
OpenStudy (anonymous):
its okay
11 years ago
jimthompson5910 (jim_thompson5910):
\[\Large r = \sqrt{a^2 + b^2}\]
\[\Large r = \sqrt{3^2 + (3\sqrt{3})^2}\]
...
...
...
\[\Large r = ??\]
11 years ago
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OpenStudy (anonymous):
r = 30?
11 years ago
OpenStudy (plasmataco):
dont think so.
11 years ago
OpenStudy (plasmataco):
simplify.
11 years ago
OpenStudy (plasmataco):
it should be somthing a lot lower
11 years ago
jimthompson5910 (jim_thompson5910):
Hint:
\[\Large (3\sqrt{3})^2=(3\sqrt{3})*(3\sqrt{3})\]
\[\Large (3\sqrt{3})^2=(3*3)*(\sqrt{3}*\sqrt{3})\]
\[\Large (3\sqrt{3})^2=(3*3)*\sqrt{3*3}\]
\[\Large (3\sqrt{3})^2=9\sqrt{9}\]
\[\Large (3\sqrt{3})^2=9*3\]
\[\Large (3\sqrt{3})^2=27\]
11 years ago
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OpenStudy (anonymous):
r = 6
11 years ago
jimthompson5910 (jim_thompson5910):
yes
11 years ago
OpenStudy (plasmataco):
yup.
11 years ago
OpenStudy (plasmataco):
horay! now my question.
11 years ago
OpenStudy (anonymous):
for theta, i got -60?
11 years ago
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jimthompson5910 (jim_thompson5910):
incorrect
11 years ago
OpenStudy (anonymous):
is the result suppose to be in radians or degrees?
11 years ago
jimthompson5910 (jim_thompson5910):
it depends on what the instructions say
11 years ago
jimthompson5910 (jim_thompson5910):
does it say which mode they want?
11 years ago
OpenStudy (anonymous):
no, but these are the answer choices
11 years ago
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jimthompson5910 (jim_thompson5910):
ok so they want radian form
11 years ago
OpenStudy (anonymous):
so would theta be - pi/3
11 years ago
jimthompson5910 (jim_thompson5910):
yes, now because our point is in Q2 (see graph) we add pi radians to our angle to land in the right quadrant
|dw:1442707471746:dw|
11 years ago
jimthompson5910 (jim_thompson5910):
- pi/3 is in Q4
|dw:1442707591362:dw|
11 years ago