Disregard the tangent stuff on the right I tried doing something else...
I would be able to read your attempt if it was typed in.
Such problems are solved by eliminating the unknown amplitude by using sin2(ωt)+cos2(ωt)=1
By the way, you weren't to see my pictures? Mhm.
You are supposed to type in your work. I can not decipher what you did from the pictures.
Do the same you did when eliminating the amplitude, but eliminate omega this time.
It is x=Asin(wt) and dx/dt= Aw cos (wt). The displacements and speeds are given at two different times.
a=A sin(wt1) u/w=Acos(wt1) -->a2+( u/w)2=A2
b=Asin(wt2) v/w=A cos(wt2) -->b2+( v/w)2=A2
Eliminate the angular frequency this time.
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