Q12:

What is the cube root of w ?

(1) The 5th root of w is 64.

(2) The 15th root of w is 4.

答案是D

不好意思 问个傻问题 什么是 第几个root的意思?

这题题目看不懂 更不用说做题了

有人可以讲一下吗 谢谢!!

cube root of w = (w)^(1/3), 5th root of w = w^(1/5), 15th root of w = w^(1/15)

想知道(w)^(1/3)是几

1) w^(1/5) = 64 => w = 64^5, 所以w^(1/3) = (64^5)^(1/3) = 4 ^ 5

2) w^(1/15) = 4 => w = 4^15, 所以w^(1/3) = (4^15)^(1/3) = 4^5

所以答案是d