Вопрос:

6. Разложите на множители: 1) \(x^2-4\); 2) \(25-9a^2\); 3) \(36m^2-100n^2\); 4) \(0,04p^2-1,69q^2\); 5) \(x^2y^2-\frac{4}{9}\); 6) \(a^4-b^6\); 7) \(0,01c^2-d^8\); 8) \(-1+a^4b^8\).

Ответ:

Используем формулу разности квадратов: \(A^2-B^2=(A-B)(A+B)\).

  1. \(x^2-4=x^2-2^2=(x-2)(x+2)\).
  2. \(25-9a^2=5^2-(3a)^2=(5-3a)(5+3a)\).
  3. \(36m^2-100n^2=(6m)^2-(10n)^2=(6m-10n)(6m+10n)\).
  4. \(0.04p^2-1.69q^2=(0.2p)^2-(1.3q)^2=(0.2p-1.3q)(0.2p+1.3q)\).
  5. \(x^2y^2-\frac{4}{9}=(xy)^2-\left(\frac{2}{3}\right)^2=\left(xy-\frac{2}{3}\right)\left(xy+\frac{2}{3}\right)\).
  6. \(a^4-b^6=(a^2)^2-(b^3)^2=(a^2-b^3)(a^2+b^3)\).
  7. \(0.01c^2-d^8=(0.1c)^2-(d^4)^2=(0.1c-d^4)(0.1c+d^4)\).
  8. \(-1+a^4b^8=(a^2b^4)^2-1^2=(a^2b^4-1)(a^2b^4+1)\).

Ответ: 1) \((x-2)(x+2)\); 2) \((5-3a)(5+3a)\); 3) \((6m-10n)(6m+10n)\); 4) \((0.2p-1.3q)(0.2p+1.3q)\); 5) \(\left(xy-\frac{2}{3}\right)\left(xy+\frac{2}{3}\right)\); 6) \((a^2-b^3)(a^2+b^3)\); 7) \((0.1c-d^4)(0.1c+d^4)\); 8) \((a^2b^4-1)(a^2b^4+1)\).