Expression 6: "y" equals 0.5 left parenthesis, "c" plus "d" , right parenthesis plus StartFraction, arcsin left parenthesis, StartNestedFraction, "x" minus 0.5 left parenthesis, "b" plus "a" , right parenthesis NestedOver 0.5 left parenthesis, "b" minus "a" , right parenthesis , EndNestedFraction , right parenthesis Over StartNestedFraction, pi NestedOver 4 , EndNestedFraction , EndFractiony=0.5c+d+arcsinx−0.5b+a0.5b−aπ4