Eight Fundamental Identities
Sec thada - Cos thada- on one side
tan thada sin thada- on the other side
How do you do this ???
http://greece.mrdonn.org/alphabet.html Impress your teacher, use the right symbols and spelling.
SecTheta-cosTheta=TanThetaSinTheta
Your teacher is just too easy.
multiply each side by cosTheta
1-cos^2 Theta=sin^2 Theta
sin^2 Theta=sin^2 Theta