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Zorluk: OrtaMultiplying Polynomials

A polynomial P(x)P(x) is defined as the product of the binomial (4x−3)(4x - 3) and the trinomial (−2x2+5x−1)(-2x^2 + 5x - 1). What is the fully expanded and simplified form of P(x)P(x)?

  1. A
    −8x3+14x2−19x−3-8x^3 + 14x^2 - 19x - 3
  2. B
    −2x2+x+3-2x^2 + x + 3
  3. −8x3+26x2−19x+3-8x^3 + 26x^2 - 19x + 3Cevap
  4. D
    −8x3−15x+3-8x^3 - 15x + 3

Cevap

−8x3+26x2−19x+3-8x^3 + 26x^2 - 19x + 3
The correct expression is found by successfully distributing both 4x4x and −3-3 across the trinomial (−2x2+5x−1)(-2x^2 + 5x - 1), maintaining correct exponents and signs, and finally combining the like terms: 20x220x^2 with 6x26x^2, and −4x-4x with −15x-15x.

Adım Adım Çözüm

1
Set up the multiplication using the distributive property.
4x(−2x2+5x−1)−3(−2x2+5x−1)4x(-2x^2 + 5x - 1) - 3(-2x^2 + 5x - 1)
Every term in the first polynomial must be multiplied by every term in the second polynomial.
2
Distribute 4x4x through the trinomial.
4x(−2x2)+4x(5x)+4x(−1)=−8x3+20x2−4x4x(-2x^2) + 4x(5x) + 4x(-1) = -8x^3 + 20x^2 - 4x
Multiply coefficients and add exponents for the variable base.
3
Distribute −3-3 through the trinomial.
−3(−2x2)−3(5x)−3(−1)=6x2−15x+3-3(-2x^2) - 3(5x) - 3(-1) = 6x^2 - 15x + 3
Multiply the constant by each term, carefully applying integer sign rules.
4
Combine the results and group like terms.
−8x3+(20x2+6x2)+(−4x−15x)+3-8x^3 + (20x^2 + 6x^2) + (-4x - 15x) + 3
Grouping terms with the same variable exponent prepares the expression for final simplification.
5
Add the coefficients of the like terms.
−8x3+26x2−19x+3-8x^3 + 26x^2 - 19x + 3
This yields the polynomial in standard form.

Anahtar Kavram

Multiplying polynomials by distributing every term in the first factor to every term in the second, then combining like terms.
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