To find the difference; subtract the coefficients of x², x and constants respectively.

Coefficient of x² in:

1^st expression is (3 + i)

2^nd expression is

Subtract the x² coefficients. i.e.,

Coefficient of x in:

1^st   expression is

2^nd expression is 

Subtract the x coefficients. i.e.,

Coefficient of Constants in:

1^st   expression is (4 + i)

1^st expression is

Subtract constants. i.e., (7 + i)

The solution is .