$A^2=A_1^2+A_2^2+2A_1A_2.\cos\left(\varphi_2-\varphi_1\right)$. | |
$A^2=A_1^2+A_2^2-2A_1A_2.\cos\left(\varphi_2-\varphi_1\right)$. | |
$A^2=A_1^2-A_2^2+2A_1A_2.\cos\left(\varphi_2-\varphi_1\right)$. | |
$A^2=A_1^2+A_2^2+2A_1A_2.\cos\left(\varphi_2+\varphi_1\right)$. |