math
posted by laura
find the standard form of the complex number shown below
9(cos 11pi/6 + isin 11pi/6)
a. 2/9  2(squareroot)3/9 i
b. 4(squareroot)3/9 + 4/9 i
c. 9/2  9(squareroot)3/2 i
d. 9(squareroot)3/2  9/2 i
e. 9(squareroot)3/4  9/4 i

Reiny
just evaluate, even if you don't have a calculator, you should be able to find
cos 11π/6 or cos 330° = cos30° = √3/2
sin 11π/6 = 1/2
9(cos 11pi/6 + i sin 11pi/6)
= 9(√3/2  1/2)
= 9√3/2  9/2 i
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