level 7
Let
be the magnitude of . Then the magnitude of is , while the magnitude of is . We get that , hence either or .
level 7
以下是解
Let
be the magnitude of
. Then the magnitude of
is
, while the magnitude of
is
. We get that
, hence either
or
.
2012年07月06日 12点07分
2
Let
be the magnitude of . Then the magnitude of is , while the magnitude of is . We get that , hence either or .
level 7
level 7
Let's now assume that
. Multiply both sides by
. The left hand side becomes
, the right hand side becomes
. Hence the solutions for this case are precisely all the
rd complex roots of unity, and there are
of those.
2012年07月06日 12点07分
4
. Multiply both sides by . The left hand side becomes , the right hand side becomes . Hence the solutions for this case are precisely all the rd complex roots of unity, and there are of those.
(a+bi)^2003 = 1，所以a+bi是1的2003次单位根，一共有2003个。加上之前a=b=0所以一共2004个解。
2012年07月06日 15点07分
level 7
![[揉脸]](/static/emoticons/u63c9u8138.png)
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同学自行百度SAT考题解释数学部分，擦SAT吊来那么难，我记得有题比较难得都可以用一元一次方程解，，，我记的是那个什么圆的周长。。
2012年07月07日 08点07分
15