## Kiran89 one year ago how two add two signal with two different frequency

Consider this $A \cos 2\pi f1+A \cos 2\pi f2$Summing or superimposing them gives the result as $2A \cos 2\pi \frac{ f1-f2 }{ 2 }\cos 2\pi \frac{ f1+f2 }{ 2 }$This is a result of simple trigonometric manipulation.