B budy New member Dec 17, 2010 #1 can someone please show me how to do this problem? thanks! if cosx=-3/5 in QIII and using -5/13 in QIII find a) cos2x b) cos(x+y)cos(x-y)
can someone please show me how to do this problem? thanks! if cosx=-3/5 in QIII and using -5/13 in QIII find a) cos2x b) cos(x+y)cos(x-y)