## Step-by-step explanation

Problem to solve:

Learn how to solve special products problems step by step online.

$a^2+2a\left(-b-c-d\right)+\left(-b-c-d\right)^2$

Learn how to solve special products problems step by step online. Expand the expression (a-b-c-d)^2. A binomial squared (difference) is equal to the square of the first term, minus the double product of the first by the second, plus the square of the second term. In other words: (a-b)^2=a^2-2ab+b^2<ul><li>Square of the first term: \left(a\right)^2 = a^2</li><li>Double product of the first by the second: 2\left(a\right)\left(-b-c-d\right) = 2a\left(-b-c-d\right)</li><li>Square of the second term: \left(-b-c-d\right)^2 = \left(-b-c-d\right)^2</li></ul>. Solve the product 2a\left(-b-c-d\right). Solve the product a\left(-2b+2\left(-c-d\right)\right). Solve the product 2a\left(-c-d\right).