Soru

Zorluk: KolayAlgebraic Exponents and Radicals

If xx is a positive real number, which of the following is equivalent to the expression (x3)2⋅x−4x8\frac{(x^3)^2 \cdot x^{-4}}{\sqrt{x^8}}?

  1. x−2x^{-2}Cevap
  2. B
    x2x^2
  3. C
    x−3x^{-3}
  4. D
    x−4x^{-4}
  5. E
    x0x^0

Cevap

The simplified expression is equivalent to x−2x^{-2}.
Applying the rules of exponents systematically yields (x3)2=x6(x^3)^2 = x^6 in the numerator, which combines with x−4x^{-4} to give x2x^2. The denominator x8\sqrt{x^8} simplifies to x8/2=x4x^{8/2} = x^4. Dividing x2x^2 by x4x^4 gives x2−4=x−2x^{2-4} = x^{-2}.

Adım Adım Çözüm

1
Simplify the power raised to a power in the numerator.
(x3)2=x3⋅2=x6(x^3)^2 = x^{3 \cdot 2} = x^6
When raising a power to a power, multiply the exponents: (am)n=am⋅n(a^m)^n = a^{m \cdot n}.
2
Multiply the terms in the numerator.
x6⋅x−4=x6+(−4)=x2x^6 \cdot x^{-4} = x^{6 + (-4)} = x^2
When multiplying exponential expressions with the same base, add the exponents: am⋅an=am+na^m \cdot a^n = a^{m+n}.
3
Simplify the radical in the denominator.
x8=(x8)12=x82=x4\sqrt{x^8} = (x^8)^{\frac{1}{2}} = x^{\frac{8}{2}} = x^4
Taking the square root of a non-negative term is equivalent to raising it to the power of 12\frac{1}{2}.
4
Divide the numerator by the denominator.
\frac{x^2}{x^4} = x^{2 - 4} = x^{-2}
When dividing exponential expressions with the same base, subtract the denominator exponent from the numerator exponent: \frac{a^m}{a^n} = a^{m-n}.

Anahtar Kavram

Laws of Exponents and Radical Simplification
Tahmini Süre:45s
Bu soruyu puanla