Control and Measurement of Unintentional Electromagnetic Radiation

APPENDIX A

USEFUL TRIGONOMETRIC IDENTITIES

A.1 BASIC IDENTITIES

A number of basic trigonometric identities that have gone into the development of the discussions in this book are presented here.

For any real numbers x and y,

By combining pairs of the above relationships, the following identities are obtained.

And, from these relationships, recalling that sin(0) = 0 and cos(0) = 1, if y = x, then

and

Then, from Eqs. A-9, A-10, and A-11, it also follows that

and

Also,

And

From Eqs. ...