Problem

Find the Product (2x+y-4z)^2

The question is asking for the calculation of the square of a trinomial expression. Specifically, you are being asked to find the product that results from squaring the expression (2x + y - 4z). Squaring this expression involves using algebraic methods such as the distributive property (FOIL - which stands for First, Outer, Inner, Last - in the case of binomials) or the expansion of a binomial squared to apply it to a trinomial. The resulting product is a quadratic expression in terms of x, y, and z.

$\left(\left(\right. 2 x + y - 4 z \left.\right)\right)^{2}$

Answer

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Solution:

Step 1:

Express $(2x + y - 4z)^2$ as $(2x + y - 4z)(2x + y - 4z)$.

Step 2:

Distribute each term in the first binomial across the second binomial: $2x(2x) + 2x(y) + 2x(-4z) + y(2x) + y(y) + y(-4z) - 4z(2x) - 4z(y) - 4z(-4z)$.

Step 3:

Simplify each term.

Step 3.1:

Apply the commutative property to rearrange terms: $2 \cdot 2x \cdot x + 2xy + 2x(-4z) + y(2x) + y \cdot y + y(-4z) - 4z(2x) - 4zy - 4z(-4z)$.

Step 3.2:

Combine like terms by adding exponents.

Step 3.2.1:

Rearrange $x$: $2 \cdot 2(x \cdot x) + 2xy + 2x(-4z) + y(2x) + y \cdot y + y(-4z) - 4z(2x) - 4zy - 4z(-4z)$.

Step 3.2.2:

Multiply $x$ by $x$: $2 \cdot 2x^2 + 2xy + 2x(-4z) + y(2x) + y \cdot y + y(-4z) - 4z(2x) - 4zy - 4z(-4z)$.

Step 3.3:

Multiply $2$ by $2$: $4x^2 + 2xy + 2x(-4z) + y(2x) + y^2 + y(-4z) - 4z(2x) - 4zy - 4z(-4z)$.

Step 3.4:

Apply the commutative property: $4x^2 + 2xy - 2 \cdot 4xz + y(2x) + y^2 + y(-4z) - 4z(2x) - 4zy - 4z(-4z)$.

Step 3.5:

Multiply $2$ by $-4$: $4x^2 + 2xy - 8xz + y(2x) + y^2 + y(-4z) - 4z(2x) - 4zy - 4z(-4z)$.

Step 3.6:

Apply the commutative property: $4x^2 + 2xy - 8xz + 2yx + y^2 - 4yz - 4z(2x) - 4zy - 4z(-4z)$.

Step 3.7:

Multiply $y$ by $y$: $4x^2 + 2xy - 8xz + 2yx + y^2 - 4yz - 4z(2x) - 4zy - 4z(-4z)$.

Step 3.8:

Apply the commutative property: $4x^2 + 2xy - 8xz + 2yx + y^2 - 4yz - 4 \cdot 2zx - 4zy - 4z(-4z)$.

Step 3.9:

Multiply $-4$ by $2$: $4x^2 + 2xy - 8xz + 2yx + y^2 - 4yz - 8zx - 4zy - 4z(-4z)$.

Step 3.10:

Apply the commutative property: $4x^2 + 2xy - 8xz + 2yx + y^2 - 4yz - 8zx - 4zy - 4 \cdot -4z \cdot z$.

Step 3.11:

Multiply $z$ by $z$ by adding exponents.

Step 3.11.1:

Rearrange $z$: $4x^2 + 2xy - 8xz + 2yx + y^2 - 4yz - 8zx - 4zy - 4 \cdot -4(z \cdot z)$.

Step 3.11.2:

Multiply $z$ by $z$: $4x^2 + 2xy - 8xz + 2yx + y^2 - 4yz - 8zx - 4zy - 4 \cdot -4z^2$.

Step 3.12:

Multiply $-4$ by $-4$: $4x^2 + 2xy - 8xz + 2yx + y^2 - 4yz - 8zx - 4zy + 16z^2$.

Step 4:

Combine like terms $2xy$ and $2yx$.

Step 4.1:

Rearrange $y$: $4x^2 + 2xy + 2yx - 8xz + y^2 - 4yz - 8zx - 4zy + 16z^2$.

Step 4.2:

Add $2xy$ and $2yx$: $4x^2 + 4xy - 8xz + y^2 - 4yz - 8zx - 4zy + 16z^2$.

Step 5:

Combine like terms $-8zx$ and $-8xz$.

Step 5.1:

Rearrange $z$: $4x^2 + 4xy + y^2 - 4yz - 8xz - 8zx - 4zy + 16z^2$.

Step 5.2:

Combine $-8xz$ and $-8zx$: $4x^2 + 4xy + y^2 - 4yz - 16xz - 4zy + 16z^2$.

Step 6:

Combine like terms $-4zy$ and $-4yz$.

Step 6.1:

Rearrange $z$: $4x^2 + 4xy + y^2 - 4yz - 4zy - 16xz + 16z^2$.

Step 6.2:

Combine $-4yz$ and $-4zy$: $4x^2 + 4xy + y^2 - 8yz - 16xz + 16z^2$.

The final expanded form of $(2x + y - 4z)^2$ is $4x^2 + 4xy - 8yz - 16xz + y^2 + 16z^2$.

Knowledge Notes:

  1. Binomial Expansion: The process of expanding a binomial raised to a power involves using the distributive property to multiply each term in the first binomial by each term in the second binomial.

  2. Commutative Property of Multiplication: This property states that the order in which two numbers are multiplied does not affect the product, i.e., $ab = ba$.

  3. Multiplying Exponents: When multiplying like bases, the exponents are added, i.e., $x^a \cdot x^b = x^{a+b}$.

  4. Combining Like Terms: This involves adding or subtracting terms that have the same variable raised to the same power.

  5. Distributive Property: This property is used to multiply a single term and two or more terms inside a set of parentheses, i.e., $a(b + c) = ab + ac$.

  6. LaTeX Formatting: In the solution, LaTeX is used to format mathematical expressions, ensuring that they are clearly presented and easy to read. For example, $x^2$ is written in LaTeX as $x^2$.

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