Question

List the ordered pairs in the equivalence relations produced by these partitions of {a, b, c, d, e, f, g}: a) {a,b},{c,d},{e,f,g} b) {a}, {b}, {c, d}, {e, f }, {g} c) {a,b,c,d},{e,f,g}

Answer 1

a) {a,b} , {c,d} , {e,f,g},{a , b } = {(a,a) (b,b) (a,b) (b,a)},{c , d } = {(c,c) (d,d) (c,d) (d , c) } ,{e,f,g} = {(e,e) (e,f) (f,e) (e,g) (f,f) (f,g) ( g,e) (g,f)(g,g)}

b) { (a,a)(b,b)(c,c)(c,d)(d,c)(d,d)(e,e)(e,f)(f,e)(f,f)(g,g)

c) {(a,a)(a,b)(b,b)(b,a)(a,c)(c,a)(b,c)(c,b)(c,c)(d,a)(a,d)(b,d)(d,b)(d,c)(c,d)(d,d)(c,c)(c,f)(f,c)(f,f)(c,g)(g,c)(f,g)(g,f)(g,g)

Explanation:

a) {a,b} , {c,d} , {e,f,g}

{a , b } = {(a,a) (b,b) (a,b) (b,a)}

{c , d } = {(c,c) (d,d) (c,d) (d , c) }

{e,f,g} = {(e,e) (e,f) (f,e) (e,g) (f,f) (f,g) ( g,e) (g,f) (g,g)}

b) {a} ,{b},{c,d} ,{e,f},{g}

{ (a,a)(b,b)(c,c)(c,d)(d,c)(d,d)(e,e)(e,f)(f,e)(f,f)(g,g)}

c) {a,b,c,d},{e,f,g}

{(a,a)(a,b)(b,b)(b,a)(a,c)(c,a)(b,c)(c,b)(c,c)(d,a)(a,d)(b,d)(d,b)(d,c)(c,d)(d,d)(c,c)(c,f)(f,c)(f,f)(c,g)(g,c)(f,g)(g,f)(g,g)