x1 = 3.75sin(100*pi*t+(2*Pi)/9) x2 = 4.42sin(100*pi*t-(2*pi)/5) Express x1 + x2 in a similar form. Convert this into the equivalent form Rsin(100pt + a) where R and a are to be found.

Hello, i have 2 waveforms and have completed the rest of the question but struggling to convert into the form required, could you pleae help.

x1 = 3.75sin(100*pi*t+(2*Pi)/9)

x2 = 4.42sin(100*pi*t-(2*pi)/5)

Express x₁ + x₂ in a similar form. Convert this into the equivalent form Rsin(100pt + a) where R and a are to be found.