Expression 7: "x" equals StartFraction, left parenthesis, left parenthesis, negative 1 , right parenthesis Superscript, "k" , Baseline arcsin left parenthesis, StartNestedFraction, "d" NestedOver "a" , EndNestedFraction , right parenthesis plus "k" pi minus "c" , right parenthesis Over "b" , EndFractionx=−1karcsinda+kπ−cb