SOLUTION: f(x)=2sin(1/3x-1/6π)，x∈R,α,β∈[0,π/2],f(3α+π/2)=10/13,f(3β+2π)=6/5,please work out cos(α+β)

Algebra ->  Equations -> SOLUTION: f(x)=2sin(1/3x-1/6π)，x∈R,α,β∈[0,π/2],f(3α+π/2)=10/13,f(3β+2π)=6/5,please work out cos(α+β)      Log On