cube root of 54a^4 (simplify)?

2009-08-04 5:08 pm
please answer

回答 (5)

2009-08-04 5:16 pm
✔ 最佳答案
54 = 27x2 = 3³ x 2... right?
and
a^4 = a³ x a

so...54 a^4 = 3³a³ x 2a

and the cube root of that = 3a x ³√(2a)
2009-08-04 5:14 pm
If a radical is not a perfect cube, break it down to a cube and a co-factor is possible. Here, it is possible.

= ³√54a^4
= (³√27) (³√a³) (³√2) (³√a) (Notice that ³√27 and ³√a³ are cubes)
= 3a ³√2a (Answer)

Hope this helps.
2009-08-04 5:26 pm
³√(54a^4)
= ³√[(3^3 * a^3 * 2 * a)]
= ³√(3^3) * ³√(a^3) * ³√2 * ³√a
= 3 * a * ³√(2 * a)
= 3a³√(2a)
2009-08-04 5:17 pm
Factor the radicand, then take the cube roots of the factors.
∛(54a⁴) = ∛(3³×2×a³×a)
             = ∛(3³) × ∛2 × ∛(a³) × ∛
             = 3a ∛(2a)
2009-08-04 5:11 pm
3 2^(1/3) a^4^(1/3)


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