GWD7-12

[vivid]

Q12
What is the cube root of w ?
(1)The 5th root of w is 64.
(2)The 15th root of w is 4.

D是對的

[吳志道]

1) w^(1/5) = 64 => w = 64^5, 所以w^(1/3) = (64^5)^(1/3) =2^10
2的(6乘5 /3 =2^10)

2) w^(1/15) = 4 => w = 4^15, 所以w^(1/3) = (4^15)^(1/3) = 2^10
2的(2乘15 /3 = 2^10)

==>所以D 這表達方法 也是看題目推ㄉ >"< 英文真難 =.=+

[asicschu]

1) w^(1/5) = 64 => w = 64^5, 所以w^(1/3) = (64^5)^(1/3) =2^10
2的(6乘5 /3 =2^10)

2) w^(1/15) = 4 => w = 4^15, 所以w^(1/3) = (4^15)^(1/3) = 2^10
2的(2乘15 /3 = 2^10)

==>所以D 這表達方法 也是看題目推ㄉ >"< 英文真難 =.=+

以後請多幫忙解題唷!!
再次感謝!! ;)

[vivid]

感謝 辛苦你了 ^^
我想破頭也想不出這種解法
大家還真強

[公主]

GWD7-12
What is the cube root of w ?
(1)The 5th root of w is 64.
(2)The 15th root of w is 4.


我還是不太懂這題目的意思>_< 有誰可以救救我嗎

[poli]

cube root就是三次方根
ex:8的三次方根便是2 <===> 2的三次方是8 (2*2*2=8)

所以The 5th root of w is 64
表示w五次方根是64 <===> 64的五次方是w
64^5=(2^6)^5=2^30=w
得到w^(1/3)=2^10

另一個就是相同觀念