Question 42605
<pre><font size = 4><b>I am lost on this problem... 
radical -50 times radical -2
 ___  __
<font face = "symbol">Ö</font>-50 <font face = "symbol">Ö</font>-2

Don't fall for the trap of always multiplying under radicals first.
Don't do that!  Negative numbers under square roots must be taken
out of the radical before multiplying under them:
 ___  __      __    _        __  _        ___ 
<font face = "symbol">Ö</font>-50 <font face = "symbol">Ö</font>-2 = (i<font face = "symbol">Ö</font>50)(i<font face = "symbol">Ö</font>2) = i² <font face = "symbol">Ö</font>50 <font face = "symbol">Ö</font>2 = (-1)<font face = "symbol">Ö</font>100 = (-1)(10) = -10 


If you multiply under the radical before taking negative signs
out of square root radicals as i's on the outside, you will get
the wrong answer.

Edwin
AnlytcPhil@aol.com</pre>