Question 973278
<pre>
{{{matrix(1,12,

If,pi<=theta<2pi,and,cos(theta)=cos(1),",",what,is,the,value,of,theta,"?")}}}

the "angle 1" means 1 radian, which is about 57.3°, so 1 radian is in quadrant QI,
so cos(<font face="symbol">q</font>) is positive. 

From <font face="symbol">p</font> to 2<font face="symbol">p</font> is the region below the x-axis, which includes quadrants QIII and
QIV.  Of those two quadrants, the cosine is positive only in QIV.

The angle <font face="symbol">q</font> in QIV which has 1 radian as its reference angle is found by
subtracting 1 radian from 2<font face="symbol">p</font> (which is the same as 360°).

Answer: 2<font face="symbol">p</font> - 1

Edwin</pre>