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How do i solve this question, please help and pls explain
a³x - x⁴ + a²x² - ax³

User Carlodurso
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1 Answer

8 votes

Answer:


\huge\boxed{x(a-x)(a+x)^2}

Explanation:

In order to factor this expression, our goal is to write the expression in a way that we can factor out a term.

With the expression
a^3 x - x^4 + a^2 x^2 - ax^3, we need to note an exponent rule.


a^(b+c) = a^b a^c

Step 1:

We can use this to get each term of this expression to have a term of
x so we can factor it out.

Let's look at each term and get it so that we can factor out an x term.


  • a^3 x = x a^3 (Commutative Property)

  • x^4 = xx^3 (Since
    x^3 \cdot x^1 = x^4)

  • a^2 x^2 = a^2 \cdot xx (Since
    x^2 = x \cdot x)

  • ax^3 = a \cdot xx^2 (Since
    x^3 = x^2 \cdot x^1

With this, our equation becomes
(xa^3) - (xx^3) + (xxa^2) - (xx^2a).

We now can factor out the common term x.


x(a^3 - x^3 + xa^2 - x^2a)

Step 2:

From here, we can now factor
a^3 - x^3 + xa^2 - x^2 a

  • Rearrange the equation:
    a^3 +xa^2 - x^3 - x^2a
  • Factor out
    a^2 from
    a^3 + xa^2 which comes out to be
    a^2(a+x)
  • Factor out
    -x^2 from
    -x^3 - x^2a which comes out to be
    -x^2(x+a)
  • We now have
    a^2(a+x) - x^2(x+a)
  • Factor out the common term,
    (a+x), which comes out to be
    (a+x)(a^2 - x^2)
  • Factor
    -x^2+a^2 into
    (a+x)(a-x)
  • We now have
    (a+x) (a+x) (a-x), which is simplified to
    (a-x)(a+x)^2

Finalizing:

Since we have just factored
a^3 - x^3 + xa^2 - x^2 a and factored x out of
a^3 x - x^4 + a^2 x^2 - ax^3 in the first couple of steps, we need to have it as a factorization of x.


x(a-x)(a+x)^2

Hope this helped!

User Vikas Bhardwaj
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