Answer:
The resultant amplitude of the two waves is 2.65.
Step-by-step explanation:
Given;
amplitude of the first wave, A₁ = 1
amplitude of the second wave, A₂ = 2
phase difference of the two amplitudes, θ = 60.0°.
The resultant amplitude of two waves after interference is given by;

Therefore, the resultant amplitude of the two waves is 2.65.