Chapter 5
Chapter 5
Chapter 5
SHOW LESS
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Ch 5.4 : The Product-to-Sum Identities<br />
Proof.<br />
cos α cos β = 1<br />
[cos(α + β) + cos(α − β)]<br />
2<br />
sin α sin β = 1<br />
[cos(α − β) − cos(α + β)]<br />
2