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Kiran89
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.