Jointly continuous PDF Here are some events defined in terms of X and Y: ·{X≤Y} ·{X2+Y2≤1} ·{1≤X≤4，Y≥0} They can all be written in the form {(X,Y)E B}for some subset B of R2,Jointly continuous PDF Here are some events defined in terms of 𝑋 and 𝑌 : • 𝑋 ≤ 𝑌 • {𝑋 2+ 𝑌 2 ≤ 1} • {1 ≤ 𝑋 ≤ 4, 𝑌 ≥ 0} They can all be written in the form {(𝑋, 𝑌) ∈ 𝐵} for some subset 𝐵 of 𝑅 2 . 8