math
posted by jenny on .
Use the exact values of the sin, cos and tan of pi/3 and pi/6, and the symmetry of the graphs of sin, cos and tan, to find the exact values of si pi/6, cos 5/3pi and tan 4pi/3.
I have found the answers to the first three using the special tables
sin(ƒÎ/6) = cos(ƒÎ/3) = 1/2
cos(ƒÎ/6) = sin(ƒÎ/3) = ã3/2
tan(ƒÎ/3) = ã3
tan(ƒÎ/6) = 1/ã3
I know that the symmetry of sin(pi/6 is in the third quadrant, so 7pi/6 =
 0.5
the symmetry of cos 5pi/3 i have taken 2pi  5pi/3 to give cos pi/3 = 0.5 but i am not too sure where the symmetry comes in
With the tan I do not quite know where to start. Maybe pi + pi/3.
As for plotting the graphs of sin,cos and tan; I do not know where to start here using the pi radians (whereas as usually I am good at plotting graphs. (perhaps it is an age thing :(

Your symbols baffle me. Sorry.

what symbols

You have been using alt251 for squareroot, which probably works for Microsoft Word, but not for this forum which requires HTML codes.
For π, type in
& p i ;
(without the spaces inbetween) and for
squareroot, use
& r a d i c ;