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anonymous
 one year ago
Can someone explain how to express 4 in trigonometric form? Really lost. Thank you!
anonymous
 one year ago
Can someone explain how to express 4 in trigonometric form? Really lost. Thank you!

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jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2Polar form: \(\Large (r,\theta)\) Trig form: \(\Large r[\cos(\theta) + i*\sin(\theta)]\) The two forms are very similar

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2write 4 as 4+0i that is in the form a+bi

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2a = 4 b = 0 plug those values into the formulas r = sqrt(a^2 + b^2) theta = arctan(b/a)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So r = 4 and theta = 0?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2r = 4 is correct but theta = 0 is not

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2dw:1437696080574:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Isn't 0/4 equal to 0, and the arctan(0) just 0?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2arctan(b/a) = arctan(0/(4)) = 0 is true but we're in the wrong spot add on 180 degrees dw:1437696139033:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So is r = 4 and theta = 4...?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2theta = 180 degrees = pi radians

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Ok so let me try and see if I can get the answer.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0A. 4(cos0degrees + i sin270degrees) B. 4(cos90degrees + i sin90degrees) C. 4(cos0degrees + i sin0degrees) D. 4(cos180degrees + i sin180degrees) Would it be D?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2The trig form, in radians, is \(\Large 4[\cos(\pi) + i*\sin(\pi)]\) that's equivalent to \(\Large 4[\cos(180^{\circ}) + i*\sin(180^{\circ})]\)

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2you are correct

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Thank you! I'll Medal you (:

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2you're welcome

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Could you help me do the same thing for 6i?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.26i = 0 + (6i) now a = 0 and b = 6

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2use the formulas r = sqrt(a^2 + b^2) theta = arctan(b/a)

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2draw a graph to make sure you get the theta in the right spot

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So would theta = pi?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2what is the value of b/a this time?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2where is tan(theta) undefined?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Isn't it at 90 degrees and 270 degrees?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2dw:1437697203957:dw

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2dw:1437697245770:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Therefore making the answer: 6(cos270degrees + i sin270degrees)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Thank you so much, could you help me with just one more? I think I understand how to do a single number, but am not sure how to do an equation?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2what's the question

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2that's not an equation. An equation needs an = sign

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Sorry, meant expression.

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2compare a+bi with 33i to see that a = 3 and b = 3

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oh ok! So then r = 3SqRt2 and theta = 1 ... but I'm still confused as to how you find the theta degree value.

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2theta is not 1

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2b/a = 1, that is true

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2arctan(b/a) = arctan(1) = ??

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So would the answer be: 3SqRt2(cos7pi/4 + i sin7pi/4) ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Thank you so much. I finally understand this!! (: You really helped me understand this, if I could give you more medals I definitely would.

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2that would be the radian form

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.2you're welcome

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Yes, that is what the answers are listed as.
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