<p>In terms of i?</p>
<p>the answer is like 6.9-4i (rectangular form)</p>
<p>Wait, isn't it -6.9 + 4i?</p>
<p>no..that's not what the book says...but how do you get near there?</p>
<p>Oh... 150degr is like 30degr, over the y-axis, a standard location on the unit circle. So cos150 would be -(root3)/2 (which is approx -.866), and sin150 would be 1/2.</p>
<p>8(cos150 + i sin150) makes it 8(-0.866+0.5i) = -6.9 + 4i.</p>
<p>Thanks!:-)</p>
<p>Any time :)</p>
<p>We had a whole chunk of a chapter on that stuff.</p>