表达式2: StartFraction, 10sin left parenthesis, "x" times StartNestedFraction, "v" NestedOver 4 pi , EndNestedFraction , right parenthesis Over StartRoot, 5 minus 4cos left parenthesis, "x" times StartNestedFraction, "v" NestedOver 4 pi , EndNestedFraction , right parenthesis , EndRoot , EndFraction10sinx·v4π5−4cosx·v4π