The solution is 
Explanation:
The expression is 
The square of a binomial is always a trinomial.
To determine the square of a binomial we shall use the formula.
The formula to find the square of a binomial is

Let us use this formula to multiply the expression 
Here
and 
Substituting the values in the formula, we get,

Squaring each term, we have,

Multiplying the product of two terms, we get,

Thus, the solution is 