<p>Okay this isn't exactly SAT I but its for SAT II Math 2...but no one really checks it so...</p>
<p>Write the complex number 4-7i in polar coordinates:</p>
<p>I think it is sqr(65)[cis(-60.25)] but the answer says sqr(65)[cis(299.7)]</p>
<p>Who's right?</p>
<p>sqrt65cos299.7 + i x sqrt65sin299.7
What is cis?</p>
<p>cis= cos(x) + isin(x)</p>
<p>could you pleas explain to me why? thanks :)</p>
<p>You got the same thing, just make the -60.25 positive by adding another 360 degrees.</p>
<p>oh oops!...wow. thanks :)</p>