S spakfilla Member Joined Feb 26, 2010 Messages 43 Gender Male HSC 2011 Jun 17, 2010 #1 Solve (show working) tan (x+y) + tan (x-y) 1- tan (x+y) tan (x-y) I forget!!!!
MATHSCAPE Member Joined Apr 21, 2009 Messages 157 Gender Male HSC 2011 Jun 17, 2010 #2 tan [(x+y)+(x-y)] = tan 2x
F fullonoob fail engrish? unpossible! Joined Jul 19, 2008 Messages 465 Gender Male HSC 2010 Jun 17, 2010 #3 tan (x+y) + tan (x-y) / 1- tan (x+y) tan (x-y) = tan [(x+y) + (x-y)] , using tan (A+B) = tanA + tanB / 1-tanAtanB = tan (2x)
tan (x+y) + tan (x-y) / 1- tan (x+y) tan (x-y) = tan [(x+y) + (x-y)] , using tan (A+B) = tanA + tanB / 1-tanAtanB = tan (2x)
