The nth Root and Fractional Indices

Learn what an nth root is and how to simplify fractional indices, like . Let’s get started! 🚀

The nth Root and Fractional Indices - introduction visual

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Square, cube, and fourth root examples showing nth root calculations and corresponding powersCube root of 8 equals 2, showing nth root rule: multiplying n roots of a number returns the original value.Cube root of 8 equals 2, showing ∛8·∛8·∛8 = 8 and fractional indices rule a^(1/n) = ⁿ√a.Cube root of 125 using fractional indices: 125 to the power ⅓ = ³√125 = 5, since 5³ = 125Fractional indices rule a^(m/n) with worked example 125^(2/3) = 25 using roots and powersFractional indices example: 16^(3/4) step by step — fourth root of 16 is 2, then 2^3 = 8

🛎️ nᵗʰ Root

  • The nᵗʰ root means a number that is multiplied by itself times.
  • For example, the cube root of 27 is 3 because .

🛎️ Rules of the nᵗʰ Root

  • The algebraic rule is when multiplied times.
  • For example, .

🛎️ Roots as Fractional Indices

  • A fractional index is another way to write a root.
  • The rule is

🛎️ Example:

  • The fractional index means take the cube root.
  • because .

🛎️ Fractional Indices Rule

  • In , the denominator tells you the root.
  • The numerator tells you the power.

🛎️ Example:

  • Find the 4th root of 16 to get 2.
  • Then raise it to the power 3 to get 8.

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Simplifying nth roots and fractional indices

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